bazel: Add rules_fuzzing to WORKSPACE

* `quickstart/bazel` depends on `pw_malloc`...
* which will soon depend on `pw_allocator`...
* which depends on `pw_metric`...
* which depends on `pw_tokenizer`...
* whose BUILD.bazel file loads pw_fuzzer/fuzzer.bzl...
* which references @@rules_fuzzing.

Change-Id: I0b8ae6799051da9069415ec295235400a3557bed
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/quickstart/bazel/+/212794
Commit-Queue: Aaron Green <aarongreen@google.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Reviewed-by: Armando Montanez <amontanez@google.com>

WORKSPACE

diff --git a/WORKSPACE b/WORKSPACE
index c9ce346..490c21f 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -65,6 +65,21 @@
 
 protobuf_deps()
 
+# TODO(b/311746469): Switch back to a released version when possible.
+git_repository(
+    name = "rules_fuzzing",
+    commit = "67ba0264c46c173a75825f2ae0a0b4b9b17c5e59",
+    remote = "https://github.com/bazelbuild/rules_fuzzing",
+)
+
+load("@rules_fuzzing//fuzzing:repositories.bzl", "rules_fuzzing_dependencies")
+
+rules_fuzzing_dependencies()
+
+load("@rules_fuzzing//fuzzing:init.bzl", "rules_fuzzing_init")
+
+rules_fuzzing_init()
+
 # Add Pigweed itself, as a submodule.
 #
 # We use a submodule for simpler integration with our CI. You can use