Fix merge rules for XLA pin updates (#102844)
https://github.com/pytorch/pytorch/pull/102446 moved the job to 12xlarge runner, but merge rule still refer to it as 4xlarge, which results in merge timeouts, for example see https://github.com/pytorch/pytorch/actions/runs/5150076112/jobs/9273821855
Pull Request resolved: https://github.com/pytorch/pytorch/pull/102844
Approved by: https://github.com/DanilBaibak, https://github.com/jeanschmidt
