Remove "hash form" from alert management client-side router usage
Problem
Since #374724 (closed) we use the <base>/root/test-proj/-/alert_management/2/details/overview
for tabs in alert details.
We also support the old "hash form" <base>/root/test-proj/-/alert_management/2/details#/overview
so it redirects to the "slash form". See #374724 (comment 1143851220)
Long-term we want to only use "slash form" and remove "hash form".
Proposed solution
Remove support for "hash form".