[roll third_party/pigweed] README: Formatting

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/98600

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 5a1f043c4dea706..d7431f4e1a0acf7
Roller-URL: https://ci.chromium.org/b/8811086968159193089
Cq-Cl-Tag: roller-builder:pigweed-experimental-roller
Cq-Cl-Tag: roller-bid:8811086968159193089
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Iad66d2d238dcedf364ac4ebb0973b6a9a2ecf91a
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/98583
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 5a1f043..d7431f4 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 5a1f043c4dea70649cc9248cb7c06c57955f8218
+Subproject commit d7431f4e1a0acf7c8e63f011ec2050d1f0b02149