build: pin -std=c11 for instrument-hooks core.c #515

Job	Run time
toolchain-detection-tests	5s
bazel-build (ubuntu-latest, walltime, 8.4.2)	31s
macos-walltime-bazel-test	1m 2s
bazel-build (ubuntu-latest, walltime, 7.6.2)	35s
tests	20s
cmake-build (ubuntu-latest, walltime)	1m 8s
bazel-build (ubuntu-latest, off, 7.6.2)	39s
cmake-integration-tests (walltime, codspeed-macro)	7m 37s
cmake-build (windows-latest, off)	2m 11s
cmake-build (windows-latest, walltime)	3m 49s
lint	12s
cmake-build (ubuntu-latest, off)	1m 6s
bazel-build (ubuntu-latest, off, 8.4.2)	37s
bazel-build (ubuntu-latest, off, 9.0.0-pre.20250921.2)	1m 11s
macos-walltime-cmake-test	7m 0s
bazel-integration-tests (simulation, ubuntu-latest)	1m 40s
cmake-integration-tests (off, ubuntu-latest)	1m 11s
bazel-integration-tests (off, ubuntu-latest)	36s
bazel-integration-tests (walltime, codspeed-macro)	7m 27s
cmake-integration-tests (memory, ubuntu-latest)	1m 20s
bazel-build (windows-latest, walltime, 8.4.2)	2m 3s
bazel-integration-tests (memory, ubuntu-latest)	1m 55s
bazel-build (windows-latest, off, 8.4.2)	1m 42s
cmake-integration-tests (simulation, ubuntu-latest)	1m 36s
bazel-build (windows-latest, off, 9.0.0-pre.20250921.2)	1m 18s
bazel-build (windows-latest, walltime, 9.0.0-pre.20250921.2)	1m 4s
bazel-build (windows-latest, walltime, 7.6.2)	1m 50s
bazel-build (ubuntu-latest, walltime, 9.0.0-pre.20250921.2)	1m 8s
bazel-build (windows-latest, off, 7.6.2)	1m 27s
	54m 20s

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