Add configurable file size limits to the Maven package repository

Problem

There is currently no limit to the size of file a user can upload when publishing a Maven package to the GitLab package registry.

Solution

An admin user can set a maximum file size for Maven package files for the instance in the admin package settings section.

The default setting should be 50MB.

Technical notes

Create a plan_limits column named maven_max_file_size to manage this setting

References

Investigation of package limits