Revert "Restrict access to release branches for LTS Refresh."

This reverts commit 6a7de45994b337ac7e482b04341af4d4047dc196.

Reason for revert: LTS refresh is completed

Change-Id: Iddbdad5e627295f6dfbdf94f331177204d9d262e
Reviewed-on: https://cos-review.googlesource.com/c/All-Projects/+/166367
Tested-by: Derek Taylor <ddtaylor@google.com>
Reviewed-by: Angel Adetula <angeladetula@google.com>