refactor: Removed TestUnexistingLoop.remove_loop fixture, because it has no effect.

Under Python 3.10, the remove_loop fixture raises:
"DeprecationWarning: There is no current event loop"
This means that the remove_loop fixture effectively does nothing.

The test case is still kept, because it seemingly aims to test that the "asyncio" marker works inside test classes when no "event_loop" fixture is explicitly specified.

Signed-off-by: Michael Seifert <m.seifert@digitalernachschub.de>

Author: seifertm

tests/test_simple.py

@@ -110,15 +110,8 @@ async def test_asyncio_marker_method(self, event_loop):
 
 
 class TestUnexistingLoop:
-    @pytest.fixture
-    def remove_loop(self):
-        old_loop = asyncio.get_event_loop()
-        asyncio.set_event_loop(None)
-        yield
-        asyncio.set_event_loop(old_loop)
-
     @pytest.mark.asyncio
-    async def test_asyncio_marker_without_loop(self, remove_loop):
+    async def test_asyncio_marker_without_loop(self):
         """Test the asyncio pytest marker in a Test class."""
         ret = await async_coro()
         assert ret == "ok"