[P0] MacOS Silicon GitHub connectivity issues & RBE docker issues

[fweikert]

We're currently experiencing two unrelated outages:

• MacOS Silicon workers are unable to reach GitHub reliably
• RBE jobs fail due to a Docker permission error.

[fweikert]

MacOS arm64 workers are back online.

[fweikert]

MacOS arm64 jobs seem to be fine now. We might have a fix for the Docker issue, too, but that requires rolling out new images, which will likely happen tomorrow morning.

[UebelAndre]

@fweikert Just moments ago I started seeing the docker issue again: https://buildkite.com/bazel/bcr-presubmit/builds/37276/list?jid=019f23e7-5992-4cae-ab40-8818524d8935&tab=output

[fweikert]

It works again: https://buildkite.com/bazel/bcr-presubmit/builds/37413