Installer root fs not correctly sized

[TobiPeterG]

Describe the bug
While the BTRFS partition takes the complete free space of my USB drives, I noticed that the actual BTRFS fs takes only 5GB. A "sudo btrfs filesystem resize max /home" fixes it. You can check by running "df -h /" before and after running this command.
This prevents backups from home partitions that are larger than about 2GB.

To Reproduce
Steps to reproduce the behavior:

1. Download official Aeon image
2. Flash to USB drive
3. Boot installer
4. Run "df -h /"
5. Run "sudo btrfs filesystem resize max /home"
6. Run "df -h /"
7. Compare

Expected behavior
The installer should directly have a correctly sized fs after first boot.

Additional context
Should anything else be required, please let me know :)