[test] Removed obsolete test "test_async_close_loop".

The test simply asserts that the event loop can be closed inside a test. Given that the event_loop fixture returns a regular event loop, this test case simply tests standard-library behavior and is not needed for pytest-asyncio.

Signed-off-by: Michael Seifert <[email protected]>

Author: seifertm

Diff for: tests/test_simple.py

@@ -300,10 +300,6 @@ async def test_no_warning_on_skip():
     result.assert_outcomes(skipped=1)
 
 
-def test_async_close_loop(event_loop):
-    event_loop.close()
-
-
 def test_warn_asyncio_marker_for_regular_func(testdir):
     testdir.makepyfile(
         dedent(