[roll third_party/pigweed] pw_protobuf: Add common_py_pb2 target

Original-Bug: b/309351244
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/182650

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 8b5d45a34aa2d4b..2fda6c82d5b6004
Roller-URL: https://ci.chromium.org/b/8763257417206190401
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ia61c590bcd3a9fb4b0ddca3c02e206452a1bfac2
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/182670
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index 8b5d45a..2fda6c8 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 8b5d45a34aa2d4b30a8624a6df946077c879b892
+Subproject commit 2fda6c82d5b60041e24f285af6e1a707114bcd9d