[10.0] Target loc back to main after we're done with 9.0

[carlossanlop]

We should do this right after we snap rc1.

Basically do what we did in 8.0: #90812

And then revert it after we ship 9.0 like we did here:
#95014

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Issue Details

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We should do this right after we snap rc1.

Basically do what we did in 8.0: #90812

And then revert it after we ship 9.0 like we did here:
#95014

Author:	carlossanlop
Assignees:	-
Labels:	area-Infrastructure-libraries, blocking-release
Milestone:	9.0.0

[akoeplinger]

I don't think we need to follow #90812 exactly since we (hopefully) don't need to disable OneLoc on main.

The only change needed should be setting MirrorBranch: release/9.0 in the release/9.0 branch.

[ericstj]

Ping @carlossanlop - I think you did this?

[carlossanlop]

Yep, this is done. We're getting the Loc PRs created to the release/9.0 branch: #106995

Let's keep this open so that we remember to restore the Loc branch to main after we release.

[ericstj]

Ok, since this is tracking work post-release I'll move to the 10.0.0 milestone.