Fix composer 2.0 deprecation notices

[kaidesu]

Describe the issue

We should go through and fix the remaining deprecation notices being thrown by Composer in anticipation of upgrading to Composer v2.0 down the road.

To reproduce

• Run composer install, composer update, or composer dump-autoload

Screenshots

Version and browser

Version: Beta 5

Bug report checklist

• I have filled out as much information as I can
• I have detailed how the issue can be reproduced
• I have searched for existing issues and to the best of my knowledge this is not a duplicate