Force default host on windows to the default TCP host (instead of npipe)

Signed-off-by: Joffrey F <joffrey@docker.com>

tests/unit/cli/docker_client_test.py

@@ -60,6 +60,14 @@ class DockerClientTestCase(unittest.TestCase):
         )
         self.assertEqual(client.headers['User-Agent'], expected)
 
+    @mock.patch.dict(os.environ)
+    def test_docker_client_default_windows_host(self):
+        with mock.patch('compose.cli.docker_client.IS_WINDOWS_PLATFORM', True):
+            if 'DOCKER_HOST' in os.environ:
+                del os.environ['DOCKER_HOST']
+            client = docker_client(os.environ)
+            assert client.base_url == 'http://127.0.0.1:2375'
+
 
 class TLSConfigTestCase(unittest.TestCase):
     ca_cert = 'tests/fixtures/tls/ca.pem'