tests/run-tests.py: Consider tests ending in _async.py as async tests.

The test `micropython/ringio_async.py` is a test that requires async
keyword support, and will fail with SyntaxError on targets that don't
support async/await.  Really it should be skipped on such targets, and this
commit makes sure that's the case.

Signed-off-by: Damien George <damien@micropython.org>

Author: dpgeorge

tests/run-tests.py

@@ -886,7 +886,7 @@ def run_one_test(test_file):
         is_bytearray = test_name.startswith("bytearray") or test_name.endswith("_bytearray")
         is_set_type = test_name.startswith(("set_", "frozenset")) or test_name.endswith("_set")
         is_slice = test_name.find("slice") != -1 or test_name in misc_slice_tests
-        is_async = test_name.startswith(("async_", "asyncio_"))
+        is_async = test_name.startswith(("async_", "asyncio_")) or test_name.endswith("_async")
         is_const = test_name.startswith("const")
         is_io_module = test_name.startswith("io_")
         is_fstring = test_name.startswith("string_fstring")