roll: pigweed pw_bluetooth_proxy: Use std::lock_guard

Now that pwrev.dev/248713 has landed without issue, use
std::lock_guard instead of manually locking/unlocking.

Original-Fixed: 350009505
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/249592
Presubmit-Verified: CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com>
Original-Revision: 67bef9ad55a00524ad1d66096cad23dcf78d300c

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 0942b69025f298..67bef9ad55a005
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8730897219341228305
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I3748417998fb73413546946e911221edfbef28dc
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/quickstart/bazel/+/249892
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/MODULE.bazel b/MODULE.bazel
index af09e8c..353e3ab 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -48,8 +48,8 @@
     module_name = "pigweed",
     # ROLL: Warning: this entry is automatically updated.
     # ROLL: Last updated 2024-11-18.
-    # ROLL: By https://cr-buildbucket.appspot.com/build/8730908256887283937.
-    commit = "0942b69025f2987ca9512141fe3cf3a7046f042c",
+    # ROLL: By https://cr-buildbucket.appspot.com/build/8730897219341228305.
+    commit = "67bef9ad55a00524ad1d66096cad23dcf78d300c",
     remote = "https://pigweed.googlesource.com/pigweed/pigweed",
 )
 
@@ -57,8 +57,8 @@
     module_name = "pw_toolchain",
     # ROLL: Warning: this entry is automatically updated.
     # ROLL: Last updated 2024-11-18.
-    # ROLL: By https://cr-buildbucket.appspot.com/build/8730908256887283937.
-    commit = "0942b69025f2987ca9512141fe3cf3a7046f042c",
+    # ROLL: By https://cr-buildbucket.appspot.com/build/8730897219341228305.
+    commit = "67bef9ad55a00524ad1d66096cad23dcf78d300c",
     remote = "https://pigweed.googlesource.com/pigweed/pigweed",
     strip_prefix = "pw_toolchain_bazel",
 )