[roll third_party/pigweed] pw_presubmit: Remove transitional coverage upload

Remove the transitional coverage upload code that handled single values
in addition to tuples. It's no longer needed.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/187472

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 7235731565cecea..cba4fdeaa2e16f9
Roller-URL: https://ci.chromium.org/b/8759072872585165713
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: If1a87220bd385e7bc71d72d9db72a93294e0568e
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/187623
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.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 7235731..cba4fde 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 7235731565cecea500fa61d3488bb6a4bb887a92
+Subproject commit cba4fdeaa2e16f945db65bb0a0cd2e9fe0934450