More test-quarantine improvements (#66158)

* Update test-quarantine instructions: fix TODO and Source B issues

1. Use #aw_<temporary_id> references in [QuarantinedTest] URLs instead
   of placeholder text. The safeoutputs framework resolves these to real
   issue numbers when creating the PR.

2. Add explicit target-branch check (must be main) to Source B PR build
   filtering. Add stronger language requiring the agent to call
   pull_request_read for each PR to verify merge status and target
   branch, since the agent was skipping this check and including
   builds from open PRs targeting release branches.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Recompile

* Address PR feedback: clarify #aw_ is intermediate, fix temporary_id syntax

1. Clarify that #aw_<temporary_id> is an intermediate placeholder resolved
   by the framework before PR creation, not a contradiction with the
   numeric URL requirement.

2. Fix inconsistent syntax: temporary_id values already include the aw_
   prefix (e.g., 'aw_http2ign'), so the reference format is
   #{TEMPORARY_ID} (producing #aw_http2ign), not #aw_{TEMPORARY_ID}
   (which would produce #aw_aw_http2ign).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Require full build URLs in PR bodies instead of plain build numbers

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: wtgodbe

.github/aw/actions-lock.json

@@ -29,6 +29,11 @@
       "repo": "github/gh-aw-actions/setup",
       "version": "v0.65.6",
       "sha": "31130b20a8fd3ef263acbe2091267c0aace07e09"
+    },
+    "github/gh-aw-actions/setup@v0.66.1": {
+      "repo": "github/gh-aw-actions/setup",
+      "version": "v0.66.1",
+      "sha": "73ae9ce231580f337133352d321d42b6bf54b6a9"
     }
   }
 }