[roll pigweed] pw_build: Fix python_metadata_deps

python_metadata_deps in the pw_python_action template should
automatically depend on the ._package_metadata subtarget rather than
relying on the invoker to do this.

Switch python_metadata_deps in docs/BUILD.gn to point to
pw_env_setup:core_pigweed_python_packages. This will set the
PYTHONPATH to include every dep in that package when sphinx is run.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/106919

https://pigweed.googlesource.com/pigweed/pigweed
pigweed Rolled-Commits: 0e48ef2f72f55eb..9201c46264e5e52
Roller-URL: https://ci.chromium.org/b/8805542395736076289
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ic1fe5e73a729915907b9ab5371dc67b7b0dfda38
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/zephyr-integration/+/107276
Commit-Queue: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
Bot-Commit: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
diff --git a/pigweed b/pigweed
index 0e48ef2..9201c46 160000
--- a/pigweed
+++ b/pigweed
@@ -1 +1 @@
-Subproject commit 0e48ef2f72f55eb67b7eb3c3d0211c868b47e767
+Subproject commit 9201c46264e5e52cc6f9aec6ec590bb2c10f8562