Link creation modal not scrollable

[kulmann]

Describe the bug

If the browser height is small I'm not able to click on the button for creating submitting the link creation modal.

Steps to reproduce

1. Have a small browser height
2. Create a file
3. Click on the "copy link" quick action in the file list
4. Type in a password so that the (rather lengthy) password rules appear

Expected behavior

The controls of the modal (Cancel and Submit buttons) are always visible

Actual behavior

The controls of the modal are not in the visible area anymore

Screenshot

Additional context

Please fix on stable-8.0.