Add a collapsible section in query editors

[idastambuk]

For optional sections in our query editors, it would be good to have a collapsible section that would work as an "EditorCollapseSection" perhaps.
Right now, if we include grafana/ui's CollapsibleSection, it interferes with EdtiorRow's Stack, and makes the title and the content of the section fall in the same flex row:

It would be good to have something like in Loki:

Right now Loki uses a custom component to render a collapsible section. A possible solution is just to copy over the code from Loki and make it available for external plugins to use.