Remove option to refer to queue selector as experimental

In #147 (closed), we changed the --experimental-queue-selector option to be just --queue-selector, but we support either. In this issue, we can remove the old version. To do so, we'll need to grep for this issue (https://gitlab.com/gitlab-com/gl-infra/scalability/-/issues/646) in:

1. The Rails app.
2. Omnibus.
3. Charts.
4. Our CNG images.

And remove / simplify as appropriate.

We also need to mention this in the monthly release post.

added to epic &198

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marked this issue as related to #147 (closed)

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mentioned in issue #538

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mentioned in merge request gitlab-org/build/CNG!548 (merged)

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@smcgivern Can we set milestone of this one to %14.0 ?

@balasankarc we can, but our goal was probably to do this later than 14.0: &198 (comment 527957721)

Do you think that will be a problem?

@smcgivern We warned in omnibus-gitlab that the flag will be removed in 14.0 - https://gitlab.com/gitlab-org/omnibus-gitlab/blob/703173d3b48a3aa8cd31494b759a61a7a50d9e92/files/gitlab-cookbooks/package/libraries/deprecations.rb#L106-117. Technically, I think we can let it run for few more releases and no one will complain about that, but when we eventually break it, we must expect at least one customer complaining.

But if we want to continue letting it run after 14.0, we should update the file I linked above to say which version we pick. Else users who still have it won't be able to upgrade to 14.0. We have automatic guards in place to ensure that users don't try to run removed configuration.

@balasankarc OK, that sounds more like of a hard constraint for this one as we have codified the release. It isn't particularly hard to make this change, and it doesn't really leave us in an inconsistent state with &198, so I'll make sure to do this in 14.0. cc @rnienaber

Starting work on this now.

changed due date to May 28, 2021

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mentioned in merge request gitlab-org/omnibus-gitlab!5306 (merged)

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mentioned in merge request gitlab-org/charts/gitlab!2023 (merged)

mentioned in merge request gitlab-org/build/CNG!679 (merged)