[roll third_party/pigweed] pw_build: Propagate public_deps in py templates

This change allows templatized targets whose innermost action has
outputs to state public_deps so that other targets can depend on the
files created by such actions.

Testing: Successfully built downstream project using this template.
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/57880

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: a6325cd15614abb..e93ccb13002325a
Roller-URL: https://ci.chromium.org/b/8837969299637678097
Cq-Cl-Tag: roller-builder:pigweed-experimental-roller
Cq-Cl-Tag: roller-bid:8837969299637678097
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I73f39a1d46a7f3238d17aa8848f5ca783f54a65e
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/58221
Bot-Commit: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
Commit-Queue: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index a6325cd..e93ccb1 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit a6325cd15614abbae094542c6e72fd548e44bc15
+Subproject commit e93ccb13002325a78690435fdd19a685d4b00e64