Fix right sidebar interaction
What does this MR do and why?
It fixes a bug where the content of the epic page did not adjust its width when right sidebar was expanded/collapsed.
As as side effect the same bug was fixed for the alert page as it uses the same toggle component.
How to set up and validate locally
- Change the page layout to Fluid under user preferences
- Navigate to some epic
- Expand/collapse right sidebar and make sure that the central content is shrinked/expanded to accommodate the sidebar
| Epic Before | Epic After | Alert After |
|---|---|---|
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Related to #406586 (closed)