Empty placeholders improperly positioned in landscape

[AlvaroBrey]

Steps to reproduce

1. Have no files
2. Put the phone in landscape

Expected behaviour

• Empty placeholder is shown in the middle of the screen, or at least is scrollable

Actual behaviour

• Empty placeholder is either cut off, or has no margin at the bottom, and scroll doesn't work

Environment data

Android version: 11

Device model: emulator (pixel4)

Stock or customized system: stock

Nextcloud app version: 3.18.0

Nextcloud server version: 22

Reverse proxy: no

[tobiasKaminsky]

First attempt for a solution: https://github.com/nextcloud/android/pull/9478