test(web-app-docs): reuse StopBuilderError in the timeout loop test and merge its nested with

Gate pass 9 on the merged store-i18n stopped at ruff N818 on the local Stop exception that the builder-timeout test defined next to the module's StopBuilderError from the build-before-clone tests, plus SIM117 on the nested with in the healthy-mirror test.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/unit/python/roles/web-app-docs/files/infinito_docs/test_build_queue.py

@@ -238,20 +238,17 @@ class TestBuilderLoop(QueueFixture, unittest.TestCase):
         attempts: list = []
         sleeps: list = []
 
-        class Stop(Exception):
-            pass
-
         def sleep(seconds):
             sleeps.append(seconds)
             if len(sleeps) > 1:
-                raise Stop
+                raise StopBuilderError
 
         clock = SimpleNamespace(monotonic=time.monotonic, sleep=sleep)
         with (
             patch.object(subprocess, "run", timed_out_clone(attempts)),
             patch.object(build_queue, "time", clock),
             redirect_stderr(io.StringIO()) as stderr,
-            self.assertRaises(Stop),
+            self.assertRaises(StopBuilderError),
         ):
             shelf.run_builder(0)
 

tests/unit/python/roles/web-app-docs/files/infinito_docs/test_library.py

@@ -347,11 +347,13 @@ class TestClone(LibraryFixture):
         )
         shelf.fetch()
         attempts: list = []
-        with patch.object(
-            subprocess, "run", timed_out_clone(attempts, unresolved_head=True)
+        with (
+            patch.object(
+                subprocess, "run", timed_out_clone(attempts, unresolved_head=True)
+            ),
+            self.assertRaises(subprocess.TimeoutExpired),
         ):
-            with self.assertRaises(subprocess.TimeoutExpired):
-                shelf.fetch()
+            shelf.fetch()
 
         self.assertEqual(len(attempts), 1)
         self.assertEqual(