[roll third_party/pigweed] pw_env_setup: Change ninja cipd path and version

Original-Bug: 458
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/58320

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: a8a6f474fed9ed9..6818b09d77da0b6
Roller-URL: https://ci.chromium.org/b/8837867785269101905
Cq-Cl-Tag: roller-builder:pigweed-sample-project-roller
Cq-Cl-Tag: roller-bid:8837867785269101905
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Icb9befe79470473a4485045f26eb15966704ea55
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/sample_project/+/58340
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 a8a6f47..6818b09 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit a8a6f474fed9ed905ae597476d8d1701500fe5f7
+Subproject commit 6818b09d77da0b692f8a83c22f973c2862f8c8e3