Draft: Remove update.js.haml as it is not used

What does this MR do?

related to: #250837 (closed)

Removes app/views/projects/update.js.haml as it is not being used anymore.

Screenshots (strongly suggested)

n/a

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides