Removed target blank from the environments component

What does this MR do?

Removes the target="_blank" from the metrics button component inside the environments list

Why was this MR needed?

Opening the metrics view from the environments list opened in a new tab, but since we were not leaving GitLab we want it to open on the same tab to keep the UX consistent

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Tests
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

closes #31029 (closed)