roll: pigweed pw_chrono: Properly stamp build time in Bazel

Before this change, the generated build_time.h header would be
unconditionally cached between builds. This means the time in
build_time.h would reflect not the actual time when the build command
was run, but the time when the cached version of the file was built,
which could have been in the distant past.

After this change the caching behavior depends on how Bazel is invoked:

1. By default, the file is cached as before.
2. If Bazel is invoked with the --stamp flag, the file will be rebuilt.
   This option should be used for release builds.

Fixes: 367739962
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/237809
Presubmit-Verified: CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com>
Original-Revision: 279ab4a35543900b62e674d14c2e663532ad5a18

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 974dd9e7201646..279ab4a3554390
Roller-URL: https://ci.chromium.org/b/8735170122760915649
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I154208a2db9e88b4f84e51fb0ab526b984143fb8
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/quickstart/bazel/+/239315
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
diff --git a/MODULE.bazel b/MODULE.bazel
index 7e749e2..d89b93b 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -49,8 +49,8 @@
     module_name = "pigweed",
     # ROLL: Warning: this entry is automatically updated.
     # ROLL: Last updated 2024-10-02.
-    # ROLL: By https://cr-buildbucket.appspot.com/build/8735171074488016337.
-    commit = "974dd9e72016464ee28f2831086ea6f561257939",
+    # ROLL: By https://cr-buildbucket.appspot.com/build/8735170122760915649.
+    commit = "279ab4a35543900b62e674d14c2e663532ad5a18",
     remote = "https://pigweed.googlesource.com/pigweed/pigweed",
 )
 
@@ -58,8 +58,8 @@
     module_name = "pw_toolchain",
     # ROLL: Warning: this entry is automatically updated.
     # ROLL: Last updated 2024-10-02.
-    # ROLL: By https://cr-buildbucket.appspot.com/build/8735171074488016337.
-    commit = "974dd9e72016464ee28f2831086ea6f561257939",
+    # ROLL: By https://cr-buildbucket.appspot.com/build/8735170122760915649.
+    commit = "279ab4a35543900b62e674d14c2e663532ad5a18",
     remote = "https://pigweed.googlesource.com/pigweed/pigweed",
     strip_prefix = "pw_toolchain_bazel",
 )