Accessibility - Keyboard users can not access the global issue nav sidebar when it's undocked/collapsed

Issue Summary

1. When using keyboard, it is not possible to reach the global issue nav sidebar when collapsed /undocked (getting skipped)
2. When global issue nav sidebar is open/docked, it shows tooltip as - Undock the filter panel so it is hidden when not being focused (Type '[') When using screen reader, it doesn't reads out the keyboard shortcut info in this case (Type '[' )
   reads it as blank instead of square bracket.

Steps to Reproduce

1. Go to Search for Issues page
2. Collapse the issue nav sidebar
3. Using only the keyboard, press <tab> until the focus is on the sidebar

Expected Results

1. Able to reach/navigate to sidebar & hit <enter> to open/dock the sidebar
2. Screen reader in both dock/undock state- should read the tooltip with keyboard shortcut info 

Actual Results

• We can not access the global issue nav sidebar when collapsed using the keyboard

Workaround

Should know the keyboard shortcut (pressing [)