Replace kaminari_route_prefix gem with initializer patch

[dlpierce]

Fixes spec/views/hyrax/users/index.html.erb_spec.rb on Ruby 3

kaminari_route_prefix is not Ruby 3 compatible, and the engine routing feature it supplies is (still!) not part of kaminari core. This replaces it with an in-tree patch. The changes to views are not included as they seem unused in hyrax.

Changes proposed in this pull request:

• Remove kaminari_route_prefix gem
• Add initializer patch to support the route_set option for paginate

Guidance for testing, such as acceptance criteria or new user interface behaviors:

• Pages that use kaminari pagination still function as expected

@samvera/hyrax-code-reviewers

[no-reply]

love this. barely 10 lines of inline code replacing an entire dependency is always a good call as far as i'm concerned