Revert "Grant ability to delete references to v8-admins"

This reverts commit 31eedffaf1d07989f11e6a914101c52bd1115f86.

Reason for revert: Removing this dangerous permission (was granted temporarily to delete refs/heads/6.5-lkgr as it was incorrectly created, see https://crbug.com/805439 for more details) to make sure that no-one can delete important refs like refs/heads/master just by typing one wrong command.

Original change's description:
> Grant ability to delete references to v8-admins
>
> [email protected]
>
> Change-Id: Ie505522787348bdab77e61ba9c389aa70a54ee58

[email protected],[email protected]

Change-Id: Ied3370f8b1d29a809596f1eeea2995aee6ddbd6e
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
1 file changed
tree: 8066cdc1fa3f0446ad5625e8de2f2b62ed26c7a2
  1. groups
  2. project.config