fix left border in session tabs
What does this MR do?
Fixes the missing left border in login session tabs, and removes double border in left tab.
Does this MR meet the acceptance criteria?
- Changelog entry added
- All builds are passing
- 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 #24941 (closed)