[MM-32173] Hide the experimental settings when the legacy sidebar is disabled

[devinbinnie]

Summary

When the legacy sidebar was not enabled in the System Console, and then re-enabled afterwards, the existing settings for the experimental channel organization, auto closing DMs, and any other setting dependent on the old sidebar would be blown away and reset to false.

This PR instead hides those settings so that they aren't blown away when the user updates the config and those settings become re-enabled.

Ticket Link

https://mattermost.atlassian.net/browse/MM-32173

[jgilliam17]

Thanks @devinbinnie
Tested, looks good to merge.

• Verified legacy related settings are hidden when legacy sidebar is disabled. Previously configured legacy sidebar settings are shown again and remembered (no longer reset to false) when legacy sidebar is re-enabled.

[esethna]

@amyblais for v5.32 ^

[mattermod]

Cherry pick is scheduled.

[mm-cloud-bot]

Test server destroyed

[mm-cloud-bot]

Test server destroyed

[mattermod]

Error trying doing the automated Cherry picking. Please do this manually

+++ Updating remotes...
Fetching upstream
Failed to add the RSA host key for IP address '140.82.113.4' to the list of known hosts (/app/.ssh/known_hosts).
From github.com:mattermost/mattermost-webapp
 * [new branch]          MM-18893-user-to-member -> upstream/MM-18893-user-to-member
   468d48934..2626b7b8c  MM-20437-migrate-close-channel-to-ts -> upstream/MM-20437-migrate-close-channel-to-ts
 * [new branch]          MM-27927-test       -> upstream/MM-27927-test
   848c16fe7..2fedb1a7e  MM-29027/add_shared_channels_on_admin -> upstream/MM-29027/add_shared_channels_on_admin
 * [new branch]          MM-29935-update-pricing-visibility -> upstream/MM-29935-update-pricing-visibility
   554e887a8..7d17bc933  MM-30389            -> upstream/MM-30389
 * [new branch]          MM-31791-SupportPacketGeneration -> upstream/MM-31791-SupportPacketGeneration
 * [new branch]          MM-31914-use-new-renewal-link -> upstream/MM-31914-use-new-renewal-link
 * [new branch]          MM-32192_fix-team-button-mention-badge -> upstream/MM-32192_fix-team-button-mention-badge
   df97bb9b1..e3b9e6bb7  MM24072-add-again-PR7082 -> upstream/MM24072-add-again-PR7082
   8350f9cbc..2fdf2376d  cloud               -> upstream/cloud
 * [new branch]          disablecomp         -> upstream/disablecomp
   1ad4c4a2d..4716206ff  feature/cloud-apps  -> upstream/feature/cloud-apps
   ff0522c9a..f2fea6dbd  feature/collapsed-reply-threads -> upstream/feature/collapsed-reply-threads
 * [new branch]          icon-font-update-example -> upstream/icon-font-update-example
 * [new branch]          lev-fixed-autocomplete-no-fields -> upstream/lev-fixed-autocomplete-no-fields
 + 8f904efb5...bda8fa735 marketplace_phase-3 -> upstream/marketplace_phase-3  (forced update)
   b697a0f6e..dfb8860bd  master              -> upstream/master
   28f5b4ec1..1790ddf00  release-5.25        -> upstream/release-5.25
   69386f97d..bf526913e  release-5.29        -> upstream/release-5.29
   3ce36ea77..0c35d6111  release-5.30        -> upstream/release-5.30
   cb47f7f09..3beab88d5  release-5.31        -> upstream/release-5.31
 * [new branch]          rm-nm-from-cache    -> upstream/rm-nm-from-cache
 * [new tag]             v5.29.2             -> v5.29.2
 * [new tag]             v5.30.2             -> v5.30.2
 * [new tag]             v5.31.0             -> v5.31.0
Fetching origin
Failed to add the RSA host key for IP address '140.82.113.4' to the list of known hosts (/app/.ssh/known_hosts).
+++ Updating remotes done...
!!! 'upstream/release-5.32' not found. The second argument should be something like upstream/release-0.21.
    (In particular, it needs to be a valid, existing remote branch that I can 'git checkout'.)

+++ Returning you to the master branch and cleaning up.

[amyblais]

/cherry-pick cloud

[mattermod]

Cherry pick is scheduled.