[BUGFIX] Fix documentation of "show dialog" in Workspaces

The "show dialog" option is an option
below the notification settings of
each workspace and therefor only impacts the notification settings.
A dialog will still appear, allowing the user to add a comment.
The documentation now reflects this.

Releases: main, 12.4, 11.5
Resolves: #101255
Resolves: #84629
Change-Id: I16b4d80cb454f77afe9fb0e8783920b41e3991ce
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/79783


Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>