Clean up duplicated retry function in common.sh (#96682)
I just realize that this `retry` function is defined twice in:
* https://github.com/pytorch/pytorch/blob/master/.ci/pytorch/common_utils.sh#L12-L14
* and https://github.com/pytorch/pytorch/blob/master/.ci/pytorch/common.sh#L26-L28
Also they step on each other toes as `common.sh` load `common_utils.sh` in https://github.com/pytorch/pytorch/blob/master/.ci/pytorch/common.sh#L5
This will keep only the definition in `common_utils.sh` where it should be.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/96682
Approved by: https://github.com/clee2000
