Renamed CI gate job to the org-standard "Required checks pass"

Branch protection currently requires the check named "All tests pass",
which couples the ruleset to this repo's particular CI naming. The org
is standardizing every repository on a single stable aggregator check
named "Required checks pass", so rulesets can be managed uniformly and
never silently break when individual CI jobs are renamed or matrixed.

The branch ruleset is being updated in the same pass to require the new
check name, so this PR must go green on the new gate before merge.

Author: aileen

.github/workflows/test.yml

@@ -32,8 +32,8 @@ jobs:
 
       - run: pnpm exec gscan --fatal --verbose .
 
-  all-tests-pass:
-    name: All tests pass
+  required-checks-pass:
+    name: Required checks pass
     if: always()
     needs: [test]
     runs-on: ubuntu-latest