cleanup: remove gha CI

It overlaps with 'bazel ci' running on Buildkite

.github/workflows/ci.bazelrc

diff --git a/.github/workflows/ci.bazelrc b/.github/workflows/ci.bazelrc
deleted file mode 100644
index a21ece4..0000000
--- a/.github/workflows/ci.bazelrc
+++ /dev/null
@@ -1,13 +0,0 @@
-# This file contains Bazel settings to apply on CI only.
-# It is referenced with a --bazelrc option in the call to bazel in ci.yaml
-
-# Debug where options came from
-build --announce_rc
-# This directory is configured in GitHub actions to be persisted between runs.
-build --disk_cache=~/.cache/bazel
-build --repository_cache=~/.cache/bazel-repo
-# Don't rely on test logs being easily accessible from the test runner,
-# though it makes the log noisier.
-test --test_output=errors
-# Allows tests to run bazelisk-in-bazel, since this is the cache folder used
-test --test_env=XDG_CACHE_HOME

.github/workflows/ci.yaml

diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
deleted file mode 100644
index caddff9..0000000
--- a/.github/workflows/ci.yaml
+++ /dev/null
@@ -1,22 +0,0 @@
-name: CI
-
-# Controls when the action will run.
-on:
-  # Triggers the workflow on push or pull request events but only for the main branch
-  push:
-    branches: [main, 6.x]
-  pull_request:
-    branches: [main, 6.x]
-  # Allows you to run this workflow manually from the Actions tab
-  workflow_dispatch:
-
-concurrency:
-  # Cancel previous actions from the same PR: https://stackoverflow.com/a/72408109
-  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
-  cancel-in-progress: true
-
-jobs:
-  test:
-    uses: bazel-contrib/.github/.github/workflows/bazel.yaml@v2
-    with:
-      folders: '[".", "e2e/smoke", "e2e/nodejs_host"]'