Upload img dimensions

What does this MR do?

It improves the lazy loading experience for future uploads.

• If it is an image it takes from dropzone.js the image width + height and appends it to the URL as request parameters
• Markdown Lazy Image Load Transformer is enhanced to look out for the query parameters + sets then the JS based on this

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

• Ninja CSS for keeping the size in the aspect ratio

Why was this MR needed?

• So that the transition while loading a lazy image is smoother, this is done by setting the size already on image placeholder which makes it much smoother during loading.

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Review
  • Has been reviewed by UX
  • Has been reviewed by Frontend
  • Has been reviewed by Backend
  • Has been reviewed by Database
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together

What are the relevant issue numbers?