Alignment of file picker dialog in right-to-left languages (RTL)

[elrido]

Originally reported by translator Lazerns via Crowdin:

The problem

Also this should be there :)

The solution

Ensure that the alignment matches the templates RTL mode. Bootstrap CSS should have facilities for this, we may have used the wrong CSS class.

Alternatives

Worst case, we change the alignment class based on the RTL setting PHP-side.

Additional context

Affects the two RTL translations, Arabic & Hebrew. There may be other drop downs in the menu that have similar issues.

[rugk]

Modern bootstrap seems to have some (experimental) support for it: https://getbootstrap.com/docs/5.0/getting-started/rtl/ They use https://rtlcss.com/ under-the-hood, maybe that is helpful for us too. (Also it's likely easy to migrate then, if we already use the same lib and update to bootstrap 5.)