[roll third_party/pigweed] pw_bluetooth_sapphire: Delete unused build file

Delete unused bt_gtest_package.gni GN template file. This has been
superseded by pw_test.

Fix the copyright_notice presubmit step (which was failing on
bt_gtest_package.gni).

Original-Bug: 307951383
Test:
pw presubmit --step gn_googletest_sapphire_build
pw presubmit --step copyright_notice

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/181830

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 6a45a6e8af6a171..2a963a07cfa228c
Roller-URL: https://ci.chromium.org/b/8763880273702397969
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I8d4e26784b8db7f289931cc4ac39cf6e117ddee4
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/181815
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 6a45a6e..2a963a0 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 6a45a6e8af6a1719d30633adeb21e1a4ad10ddc1
+Subproject commit 2a963a07cfa228c7f78f9cd773e3acc9d10fec87