service/sdk: Change argument from proto to string.

Proto should be confined to the api/, switch it to take the path string.

BUG=None
TEST=run_pytest

Change-Id: I1a2db886f0e9c6503dd2d6c8277666c1caca490a
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/2340244
Tested-by: Alex Klein <saklein@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Michael Mortensen <mmortensen@google.com>
Commit-Queue: Alex Klein <saklein@chromium.org>
diff --git a/api/controller/sdk_unittest.py b/api/controller/sdk_unittest.py
index afda466..1c46a99 100644
--- a/api/controller/sdk_unittest.py
+++ b/api/controller/sdk_unittest.py
@@ -191,10 +191,8 @@
     patch = self.PatchObject(sdk_service, 'UnmountPath', return_value=1)
 
     request = self._UnmountPathRequest('/test/path')
-
     sdk_controller.UnmountPath(request, self.response, self.api_config)
-    # Verify that by default sdk_service.Delete is called with force=True.
-    patch.assert_called_once_with(mock.ANY)
+    patch.assert_called_once_with('/test/path')
 
 
 class SdkUpdateTest(cros_test_lib.MockTestCase, api_config.ApiConfigMixin):