roll: third_party/pigweed Revert "roll: ninja"

This reverts commit f4fe5ccbfc7ff346e19dc118d6ecf17692e1f92d.

Reason for revert: b/451708332 causing flakes

Original-Fixed: b/451708332

Original change's description:
> roll: ninja
>
> From git_revision:1ab0e2f29818ecfc2b2ded65c463e236bf214972
> To git_revision:6a2668565aabdefd502aa64efa4b56b670b8f8ba
>
> Roll-Count: 1
> Roller-URL: https://cr-buildbucket.appspot.com/build/8701256175346321217
> GitWatcher: ignore
> CQ-Do-Not-Cancel-Tryjobs: true
> Change-Id: I2e92d4e92612151641bc2fe666c8826540e096cb
> Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/331532
> Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
> Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
> Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>

# Not skipping CQ checks because original CL landed > 1 day ago.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/332416
Original-Revision: 6bf1c5b039873b3b9fe382b1335678e3b7f50c4a

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 5e0cbcea7642fb..6bf1c5b039873b
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8701015528688137441
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: If440a489000c2e436040b53608587a92a960613b
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/examples/+/332832
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index 5e0cbce..6bf1c5b 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 5e0cbcea7642fbab005b414f0ddec680a5e198ec
+Subproject commit 6bf1c5b039873b3b9fe382b1335678e3b7f50c4a