Split Cropper.js from the main JavaScript manifest.

What does this MR do?

Splits Cropper.js from the main JavaScript file.

Are there points in the code the reviewer needs to double check?

That the avatar uploader works. (It did in my testing)

Why was this MR needed?

Smaller JS payload.

What are the relevant issue numbers?

#14372 (closed)

Does this MR meet the acceptance criteria?

• Tests
  • All builds are passing
• Conform by the style guides
• Branch has no merge conflicts with master (if you do - rebase it please)
• Squashed related commits together