Restore Tails boot splash on Buster

Builds from feature/buster now displays the Buster plymouth theme instead of our ninja theme.

From the .buildlog:

W: plymouth: The plugin label.so is missing, the selected theme might not work as expected.
W: plymouth: You might want to install the plymouth-themes package to fix this.

Feature Branch: bugfix/16743-plymouth-theme

Related issues

Has duplicate #16759 (closed)
Blocks #16209

Original created by @anonym on 16743 (Redmine)

Edited Nov 22, 2019 by intrigeri

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