WIP: Added tracking to next discussion buttons

What does this MR do?

Adds tracking to Merge request "Jump to next unresolved discussion" buttons.

Closes: #199458 (closed)

Does this MR meet the acceptance criteria?

Still need tests write up, I gave it a few shots but am not able to get the element ref in discussion_counter_spec.js could use some advice on how to finish this.

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content