Testing: use try/finally to ensure repo.json is always cleaned up

tests/test_blenderpack.py

@@ -31,11 +31,12 @@ class test_blenderpack_make_repo(unittest.TestCase):
         blenderpack.make_repo(self.helper_path / 'addons')
         repojson = self.helper_path / 'addons' / 'repo.json'
 
-        self.assertTrue(repojson.is_file())
+        try:
             with repojson.open('r') as f:
                 json.loads(f.read())
+        finally:
+            repojson.unlink()
 
-        os.remove(repojson)
         self.fail('unfinished test')
 
     def test_make_repo_from_nonexistent(self):