Adjust Create issue button on the error tracking detail page for mobile

What does this MR do?

This MR is for issue #38414 (closed) and is a frontend update.

When on the mobile screens of the error details page we now render a dropdown and clean up the alignment of the details elements.

Screenshots

Before:

After:

Does this MR meet the acceptance criteria?

Conformity

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

Availability and Testing

I have not written any tests for this MR as the application functionality has not changed and I am unsure how gitlab handles testing mobile screens so any advice on that would be awesome!

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers