[VERSION_MISMATCH]: No If-Match header found on UpdateRemoteConfig call

When calling `remoteConfigApi.projects.updateRemoteConfig(updatedRemoteConfigValue, projectName);` i am receiving the above error.

In my investigation and trial and error i found that adding `headers.putIfAbsent("If-Match", () => "etag-{ProjectNumber}-{CurrentVersion}");` to the below file at the below line fixed the issue

https://github.com/google/googleapis.dart/blob/fce266f761103c1b15b608e43989666a734271e7/discoveryapis_commons/lib/src/api_requester.dart#L217

Currently there is no way to add the etag to the call when updating a remote config value

{ProjectNumber} = The firebase project number
{CurrentVersion} = The current version of the change