chore: do run-bazel-fuzzers on non PRs (#9251)

As a follow up for b4632c0, we should
only conditionally execute `run-bazel-fuzzers` on Pull Requests but
always execute it for other events.

Author: basvandijk

.github/workflows/ci-main.yml

@@ -39,6 +39,7 @@ jobs:
           ref: ${{ inputs.commit-sha }}
       - name: Filter fuzzer related files
         uses: dorny/paths-filter@de90cc6fb38fc0963ad72b210f1f284cd68cea36 # v3
+        if: github.event_name == 'pull_request'
         id: filter
         with:
           ref: ${{ inputs.commit-sha }}
@@ -51,16 +52,16 @@ jobs:
               - "**/*.bzl"
               - "**/*.rs"
       - uses: ./.github/actions/netrc
-        if: steps.filter.outputs.fuzzers == 'true'
+        if: github.event_name != 'pull_request' || steps.filter.outputs.fuzzers == 'true'
       - name: Run Libfuzzer targets
         uses: ./.github/actions/bazel
-        if: steps.filter.outputs.fuzzers == 'true'
+        if: github.event_name != 'pull_request' || steps.filter.outputs.fuzzers == 'true'
         with:
           invocation-names: libfuzzer
           run: ./bin/fuzzing/run-all-fuzzers.sh --libfuzzer 100
       - name: Run AFL targets
         uses: ./.github/actions/bazel
-        if: steps.filter.outputs.fuzzers == 'true'
+        if: github.event_name != 'pull_request' || steps.filter.outputs.fuzzers == 'true'
         with:
           invocation-names: afl
           run: ./bin/fuzzing/run-all-fuzzers.sh --afl 10