Remove bc linter label triggers after test-infra #4956 (#120148)
After https://github.com/pytorch/test-infra/pull/4956, mergebot will not block merge for a bc linter failure that has been suppressed. The failure will be ignored instead.
This should help mitigate https://github.com/pytorch/test-infra/issues/4938 because the workflow will not be triggered multiple times when labels are attached.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/120148
Approved by: https://github.com/clee2000
