Bump third_party/pigweed/repo from `e765c4d` to `9504c03` (#29821)

Bumps [third_party/pigweed/repo](https://github.com/google/pigweed) from `e765c4d` to `9504c03`.
- [Commits](https://github.com/google/pigweed/compare/e765c4d38e33d4067f42345710ed6addc8800bce...9504c03ed4b45e81d5c72ee537565b03fb2be062)

---
updated-dependencies:
- dependency-name: third_party/pigweed/repo
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
diff --git a/third_party/pigweed/repo b/third_party/pigweed/repo
index e765c4d..9504c03 160000
--- a/third_party/pigweed/repo
+++ b/third_party/pigweed/repo
@@ -1 +1 @@
-Subproject commit e765c4d38e33d4067f42345710ed6addc8800bce
+Subproject commit 9504c03ed4b45e81d5c72ee537565b03fb2be062