[REMOVE] Support for Alliance Auth v4

[ppfeufer]

Description

Important

This app needs Alliance Auth v5!

Please make sure to update your Alliance Auth instance before you install this
version, otherwise an update to Alliance Auth will be pulled in unsupervised.

Removed

• Support for Alliance Auth v4

Type of Change:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality not to work as expected)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented on my code, particularly in hard-to-understand areas
• I have checked my code and corrected any misspellings