Actually fix ACLs on Presubmit-BoringSSL-Verified label

Think I figured out the issue. The bot needs label-* permission to add a
label, not labelAs-* (the Commit-Queue label is an exception). And human
users in fact do not need to modify the label, so I've removed their
permission.

Also adds a description that this label is informational only (does not
block submit).

Change-Id: I109092cf82c50cfd1c5ae4dd2e500a03047b561a
Reviewed-on: https://boringssl-review.googlesource.com/c/All-Projects/+/91427
Reviewed-by: Adam Langley <agl@google.com>

project.config

diff --git a/project.config b/project.config
index bcb6216..4642d96 100644
--- a/project.config
+++ b/project.config
@@ -38,8 +38,7 @@
 	label-Commit-Queue = +0..+1 group dev
 	labelAs-Commit-Queue = +0..+2 group boringssl-scoped@luci-project-accounts.iam.gserviceaccount.com
 	label-Presubmit-BoringSSL-Verified = -1..+1 group Project Owners
-	label-Presubmit-BoringSSL-Verified = -1..+1 group cria/project-boringssl-committers
-	labelAs-Presubmit-BoringSSL-Verified = -1..+1 group boringssl-scoped@luci-project-accounts.iam.gserviceaccount.com
+	label-Presubmit-BoringSSL-Verified = -1..+1 group boringssl-scoped@luci-project-accounts.iam.gserviceaccount.com
 	submit = group Project Owners
 	submit = group boringssl-scoped@luci-project-accounts.iam.gserviceaccount.com
 	submit = group cria/project-boringssl-committers
@@ -119,6 +118,7 @@
 	value = 0 No score
 	value = +1 Compiles, passes basic unit tests
 	copyCondition = changekind:NO_CHANGE OR changekind:NO_CODE_CHANGE
+	description = Informational only
 [access "refs/heads/chromium-stable"]
 	push = +force group mdb/boringssl-committers
 [access "refs/heads/master-with-bazel"]