Revert "Merge branch 'id-dependency-proxy-workhorse-inject' into 'master'"

...lers/groups/dependency_proxy_for_containers_controller.rb

app/helpers/workhorse_helper.rb

app/uploaders/dependency_proxy/file_uploader.rb

.../feature_flags/development/dependency_proxy_workhorse.yml

config/routes/group.rb

...groups/dependency_proxy_for_containers_controller_spec.rb

lib/gitlab/middleware/multipart.rb

lib/gitlab/workhorse.rb

...groups/dependency_proxy_for_containers_controller_spec.rb

spec/features/groups/dependency_proxy_for_containers_spec.rb

spec/lib/gitlab/middleware/multipart/handler_spec.rb

workhorse/internal/dependencyproxy/dependencyproxy.go

workhorse/internal/dependencyproxy/dependencyproxy_test.go

workhorse/internal/upstream/routes.go

workhorse/main_test.go