[Finishes #83811162] Allow disabling sharing pop-up in freeplay Play Lab levels
Make FreePlay + no-sharing feedback messaging consistent with other levels.
Disable 'show code' button in feedback dialog when Play Lab workspace is hidden.
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Merge pull request #630 from code-dot-org/83811162_disable_sharing_playlab_freeplay

[Delivers #83811162] Allow disabling sharing dialog in playlab freeplay