Add retry to Run Actionlint shellcheck step
Resolves a minor step of https://github.com/pytorch/pytorch/issues/71563
As we are shifting towards required status checks, it is paramount to minimize flakiness. Since this steps does a curl, there is the chance that the failure is flakiness and not the PR author's fault. This step is also around 30s so it doesn't hurt much to run 3 times.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/75610
Approved by: https://github.com/suo, https://github.com/seemethere
