Rename AWS unit tests that are not running when changing the module (#42712)

now can use `ansible-test units module_name` for the aws_s3 and aws_api_gateway modules

changes to modules/cloud/amazon/aws_api_gateway and modules/cloud/amazon/aws_s3 are not triggering the unit tests; also fix aws_s3 from importing non-exist module and skipping tests

changes to module_utils/aws/core.py are only being unit tested on modules that import from the file (if they have a corresponding test) or tests that import from the file themselves.

test/units/modules/cloud/amazon/test_aws_s3.py

@@ -3,7 +3,7 @@ import pytest
 import unittest
 
 try:
-    import ansible.modules.cloud.amazon.s3 as s3
+    import ansible.modules.cloud.amazon.aws_s3 as s3
 except ImportError:
     pytestmark = pytest.mark.skip("This test requires the s3 Python libraries")
 
@@ -24,13 +24,6 @@ class TestUrlparse(unittest.TestCase):
         actual = s3.is_fakes3("fakes3://bla.blubb")
         self.assertEqual(True, actual)
 
-    def test_is_walrus(self):
-        actual = s3.is_walrus("trulywalrus_but_invalid_url")
-        # I don't know if this makes sense, but this is the current behaviour...
-        self.assertEqual(True, actual)
-        actual = s3.is_walrus("http://notwalrus.amazonaws.com")
-        self.assertEqual(False, actual)
-
     def test_get_s3_connection(self):
         aws_connect_kwargs = dict(aws_access_key_id="access_key",
                                   aws_secret_access_key="secret_key")