Fix Windows test failures in CI (#12477)

Allow extension file names such as `native.pyd` in addition to
`native.<python-version>.<ext>`. I'm not sure why the file names have
changed, but the new file names seem okay as well.

Fixes #12460.

Author: JukkaL

mypyc/test/test_run.py

@@ -263,7 +263,7 @@ def run_case_step(self, testcase: DataDrivenTestCase, incremental_step: int) ->
 
         # Assert that an output file got created
         suffix = 'pyd' if sys.platform == 'win32' else 'so'
-        assert glob.glob('native.*.{}'.format(suffix))
+        assert glob.glob('native.*.{}'.format(suffix)) or glob.glob('native.{}'.format(suffix))
 
         driver_path = 'driver.py'
         if not os.path.isfile(driver_path):