Fix seed data for dev site

[jheretic]

Currently database seeds won't insert for the dev site. This is because the mikro-orm-based fixtures library that we use requires introspection of the database entities, but this information is not available in the final build. Some possible fixes include:

• Figure out how to include the right files or file information in the finalized bundles such that class-fixtures-factory can find the information it's looking for.
• Use the fixtures generation to create a static JSON export or a static SQL dump at buildtime while the introspection data is still present, which can be run later without having to do introspection at runtime.
• Ignore the fixtures generation and create a bespoke static dump that can be included in the docker image or volume for testing (the worst option).

[dasaderi]

We need to check if this has been done.