build: pin -std=c11 for instrument-hooks core.c #516

Job	Run time
macos-walltime-bazel-test	5m 59s
cmake-integration-tests (simulation, ubuntu-latest)	1m 42s
cmake-integration-tests (off, ubuntu-latest)	1m 2s
cmake-build (ubuntu-latest, off)	1m 7s
lint	14s
tests	26s
macos-walltime-cmake-test	5m 58s
cmake-build (windows-latest, walltime)	2m 48s
cmake-integration-tests (walltime, codspeed-macro)	12m 2s
toolchain-detection-tests	4s
cmake-integration-tests (memory, ubuntu-latest)	1m 22s
bazel-integration-tests (off, ubuntu-latest)	30s
cmake-build (windows-latest, off)	2m 22s
bazel-integration-tests (simulation, ubuntu-latest)	1m 38s
bazel-integration-tests (walltime, codspeed-macro)	7m 33s
cmake-build (ubuntu-latest, walltime)	1m 20s
bazel-integration-tests (memory, ubuntu-latest)	2m 2s
bazel-build (windows-latest, off, 8.4.2)	2m 8s
bazel-build (ubuntu-latest, off, 9.0.0-pre.20250921.2)	1m 4s
bazel-build (windows-latest, off, 9.0.0-pre.20250921.2)	2m 22s
bazel-build (ubuntu-latest, walltime, 9.0.0-pre.20250921.2)	1m 30s
bazel-build (ubuntu-latest, walltime, 8.4.2)	20s
bazel-build (windows-latest, off, 7.6.2)	2m 35s
bazel-build (windows-latest, walltime, 9.0.0-pre.20250921.2)	1m 13s
bazel-build (ubuntu-latest, off, 8.4.2)	32s
bazel-build (windows-latest, walltime, 7.6.2)	1m 33s
bazel-build (ubuntu-latest, off, 7.6.2)	31s
bazel-build (windows-latest, walltime, 8.4.2)	3m 1s
bazel-build (ubuntu-latest, walltime, 7.6.2)	39s
	1h 5m 37s

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