Feat: cross link app settings to account settings

[GretaD]

fixes #9161
Please notice that the mockup on the ticket is on the wrong modal :)
To do

• Add the account settings option to app settings modal
• Close the app settings modal when the account settings modal is opened

[GretaD]

@kesselb your suggestion worked, yaaay :)

[GVodyanov]

The only thing I could complain about is the margin-bottom: 80px for the settings section being a little exaggerated, but that's a nextcloud vue thing, I guess if designers will want it will be changed eventually

[kesselb]

I find "Settings for:" a bit redundant.