Do not wait forever for test server to start or stop

tests/conftest.py

@@ -268,7 +268,11 @@ class TestServer(Server):
             await self.startup()
 
 
-def serve_in_thread(server: TestServer) -> typing.Iterator[TestServer]:
+def serve_in_thread(
+    server: TestServer,
+    *,
+    timeout: float = 10.0,
+) -> typing.Iterator[TestServer]:
     server_exception = None
     server_caught_exception = threading.Event()
 
@@ -286,15 +290,21 @@ def serve_in_thread(server: TestServer) -> typing.Iterator[TestServer]:
     thread.start()
 
     try:
-        while not server.started:
-            if server_caught_exception.wait(1e-3):
+        start_time = time.time()
+        while True:
+            if server.started:
+                break
+            if server_caught_exception.wait(1e-3):  # pragma: nocover
                 raise RuntimeError(
                     f"Server failed to start: {server_exception!r}",
                 ) from server_exception
+            if time.time() - start_time > timeout:  # pragma: nocover
+                raise TimeoutError("Server did not start in time")
+            time.sleep(1e-3)
         yield server
     finally:
         server.should_exit = True
-        thread.join()
+        thread.join(timeout=timeout)
 
 
 @pytest.fixture(scope="session")