Drop support for Bazel 5.

This moves all our CI to Bazel 6 and drops the additional parameterization we had on Bazel version.

PiperOrigin-RevId: 551986376
diff --git a/.github/workflows/test_ruby.yml b/.github/workflows/test_ruby.yml
index 045eedf..6b6e8cc 100644
--- a/.github/workflows/test_ruby.yml
+++ b/.github/workflows/test_ruby.yml
@@ -19,16 +19,14 @@
         include:
           # Test both FFI and Native implementations on the highest and lowest
           # Ruby versions for CRuby and JRuby, but only on Bazel 5.x.
-          - { name: Ruby 2.7, ruby: ruby-2.7.0, bazel: 5.1.1, ffi: NATIVE}
-          - { name: Ruby 2.7, ruby: ruby-2.7.0, bazel: 5.1.1, ffi: FFI}
-          - { name: Ruby 3.0, ruby: ruby-3.0.2, bazel: 5.1.1}
-          - { name: Ruby 3.1, ruby: ruby-3.1.0, bazel: 5.1.1}
-          - { name: Ruby 3.2, ruby: ruby-3.2.0, bazel: 5.1.1, ffi: NATIVE}
-          - { name: Ruby 3.2, ruby: ruby-3.2.0, bazel: 5.1.1, ffi: FFI}
-          - { name: JRuby 9.4, ruby: jruby-9.4.3.0, bazel: 5.1.1, ffi: NATIVE}
-          - { name: JRuby 9.4, ruby: jruby-9.4.3.0, bazel: 5.1.1, ffi: FFI}
-          - { name: Ruby 2.7 (Bazel6), ruby: ruby-2.7.0, bazel: 6.0.0}
-          - { name: JRuby 9.4 (Bazel6), ruby: jruby-9.4.3.0, bazel: 6.0.0}
+          - { name: Ruby 2.7, ruby: ruby-2.7.0, ffi: NATIVE }
+          - { name: Ruby 2.7, ruby: ruby-2.7.0, ffi: FFI }
+          - { name: Ruby 3.0, ruby: ruby-3.0.2 }
+          - { name: Ruby 3.1, ruby: ruby-3.1.0 }
+          - { name: Ruby 3.2, ruby: ruby-3.2.0, ffi: NATIVE }
+          - { name: Ruby 3.2, ruby: ruby-3.2.0, ffi: FFI }
+          - { name: JRuby 9.4, ruby: jruby-9.4.3.0, ffi: NATIVE }
+          - { name: JRuby 9.4, ruby: jruby-9.4.3.0, ffi: FFI }
 
     name: Linux ${{ matrix.name }}${{ matrix.ffi == 'FFI' && ' FFI' || '' }}
     runs-on: ubuntu-latest
@@ -38,9 +36,9 @@
         with:
           ref: ${{ inputs.safe-checkout }}
       - name: Run tests
-        uses: protocolbuffers/protobuf-ci/bazel-docker@v1
+        uses: protocolbuffers/protobuf-ci/bazel-docker@v2
         with:
-          image: ${{ matrix.image || format('us-docker.pkg.dev/protobuf-build/containers/test/linux/ruby:{0}-{1}-508417e5215994ade7585d28ba3aad681a25fa5d', matrix.ruby, matrix.bazel) }}
+          image: ${{ matrix.image || format('us-docker.pkg.dev/protobuf-build/containers/test/linux/ruby:{0}-6.3.0-66964dc8b07b6d1fc73a5cc14e59e84c1c534cea', matrix.ruby) }}
           credentials: ${{ secrets.GAR_SERVICE_ACCOUNT }}
           bazel-cache: ruby_linux/${{ matrix.ruby }}_${{ matrix.bazel }}
           bazel: test //ruby/... //ruby/tests:ruby_version --test_env=KOKORO_RUBY_VERSION --test_env=BAZEL=true ${{ matrix.ffi == 'FFI' && '--//ruby:ffi=enabled --test_env=PROTOCOL_BUFFERS_RUBY_IMPLEMENTATION=FFI' || '' }}
@@ -56,14 +54,14 @@
 
       - name: Cross compile protoc for aarch64
         id: cross-compile
-        uses: protocolbuffers/protobuf-ci/cross-compile-protoc@v1
+        uses: protocolbuffers/protobuf-ci/cross-compile-protoc@v2
         with:
-          image: us-docker.pkg.dev/protobuf-build/containers/common/linux/bazel:5.1.1-6361b3a6e5c97e9951d03a4de28542fc45f1adab
+          image: us-docker.pkg.dev/protobuf-build/containers/common/linux/bazel:6.3.0-91a0ac83e968068672bc6001a4d474cfd9a50f1d
           credentials: ${{ secrets.GAR_SERVICE_ACCOUNT }}
           architecture: linux-aarch64
 
       - name: Run tests
-        uses: protocolbuffers/protobuf-ci/docker@v1
+        uses: protocolbuffers/protobuf-ci/docker@v2
         with:
           image: arm64v8/ruby:2.7.3-buster
           skip-staleness-check: true
@@ -109,7 +107,7 @@
         run: ruby --version | grep ${{ matrix.version }} || (echo "Invalid Ruby version - $(ruby --version)" && exit 1)
 
       - name: Run tests
-        uses: protocolbuffers/protobuf-ci/bazel@v1
+        uses: protocolbuffers/protobuf-ci/bazel@v2
         with:
           credentials: ${{ secrets.GAR_SERVICE_ACCOUNT }}
           bazel-cache: ruby_macos/${{ matrix.version }}
@@ -122,16 +120,14 @@
         include:
           # Test both FFI and Native implementations on the highest and lowest
           # Ruby versions for CRuby and JRuby, but only on Bazel 5.x.
-          - { name: Ruby 2.7, ruby: ruby-2.7.0, bazel: 5.1.1, ffi: NATIVE }
-          - { name: Ruby 2.7, ruby: ruby-2.7.0, bazel: 5.1.1, ffi: FFI }
-          - { name: Ruby 3.0, ruby: ruby-3.0.2, bazel: 5.1.1}
-          - { name: Ruby 3.1, ruby: ruby-3.1.0, bazel: 5.1.1}
-          - { name: Ruby 3.2, ruby: ruby-3.2.0, bazel: 5.1.1, ffi: NATIVE }
-          - { name: Ruby 3.2, ruby: ruby-3.2.0, bazel: 5.1.1, ffi: FFI }
-          - { name: JRuby 9.4, ruby: jruby-9.4.3.0, bazel: 5.1.1, ffi: NATIVE }
-          - { name: JRuby 9.4, ruby: jruby-9.4.3.0, bazel: 5.1.1, ffi: FFI }
-          - { name: Ruby 2.7 (Bazel6), ruby: ruby-2.7.0, bazel: 6.0.0}
-          - { name: JRuby 9.4 (Bazel6), ruby: jruby-9.4.3.0, bazel: 6.0.0}
+          - { name: Ruby 2.7, ruby: ruby-2.7.0, ffi: NATIVE }
+          - { name: Ruby 2.7, ruby: ruby-2.7.0, ffi: FFI }
+          - { name: Ruby 3.0, ruby: ruby-3.0.2}
+          - { name: Ruby 3.1, ruby: ruby-3.1.0}
+          - { name: Ruby 3.2, ruby: ruby-3.2.0, ffi: NATIVE }
+          - { name: Ruby 3.2, ruby: ruby-3.2.0, ffi: FFI }
+          - { name: JRuby 9.4, ruby: jruby-9.4.3.0, ffi: NATIVE }
+          - { name: JRuby 9.4, ruby: jruby-9.4.3.0, ffi: FFI }
     name: Install ${{ matrix.name }}${{ matrix.ffi == 'FFI' && ' FFI' || '' }}
     runs-on: ubuntu-latest
     steps:
@@ -140,9 +136,9 @@
         with:
           ref: ${{ inputs.safe-checkout }}
       - name: Run tests
-        uses: protocolbuffers/protobuf-ci/bazel-docker@v1
+        uses: protocolbuffers/protobuf-ci/bazel-docker@v2
         with:
-          image: us-docker.pkg.dev/protobuf-build/containers/test/linux/ruby:${{ matrix.ruby }}-${{ matrix.bazel }}-508417e5215994ade7585d28ba3aad681a25fa5d
+          image: us-docker.pkg.dev/protobuf-build/containers/test/linux/ruby:${{ matrix.ruby }}-6.3.0-66964dc8b07b6d1fc73a5cc14e59e84c1c534cea
           credentials: ${{ secrets.GAR_SERVICE_ACCOUNT }}
           bazel-cache: ruby_install/${{ matrix.ruby }}_${{ matrix.bazel }}
           bash: >