fix: get quota of correct file system

* Gets free space for the storage folder now
* Works with special configuration where external storage is used and user quota set to 0
* Display of total space removed as it can not be determined with certainty

fix: Favicon sometimes changed after first success login

ci: Update release description to include release notes template

Merge branch 'Bugfix-3.16.1' into 'master'

Bugfix 3.16.1

Closes #607 and #593

See merge request joendres/filelink-nextcloud!296

Release 3.16.0

Release 3.15.0

Release 3.14.0

Bugfix release 3.13.1

Release 3.13.0

Releas 3.12.0