Remove unnecessary require_relative calls from service classes.

What does this MR do?

Removes unnecessary requires.

Why was this MR needed?

Rails by default use autoload for all dirs from app folder. require_relative not needed. See ActiveSupport::Dependencies.autoload_paths

• Changelog entry added

• n/a Documentation created/updated

• Tests

  • n/a Added for this feature/bug
  • All builds are passing

• Conform by the merge request performance guides

• Conform by the style guides

• Branch has no merge conflicts with master (if it does - rebase it please)

• Squashed related commits together