Visualize: Metric vis pushes update button below fold

[flash1293]

Kibana version: 7.12 BC

Describe the bug: If a metric vis overflows the editor, it's not scrollable within the workspace, but increases the height of the side bar which pushes the update button below the fold

Steps to reproduce:

1. Configure a metric vis which will produce lots of different metrics (split plus multiple metric aggs)
2. Update button is only reachable via scroll

Expected behavior:
Update button should stay visible, only the vis workspace should become scrollable

Screenshots (if relevant):

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)

[stratoula]

This PR fixes this problem. So this will be solved on 7.13 unless it is safe to backport it on 7.12. @sulemanof wdyt?

[sulemanof]

This PR fixes this problem. So this will be solved on 7.13 unless it is safe to backport it on 7.12. @sulemanof wdyt?

I’d prefer to fix it separately.
I can’t be sure the eui resizer is safe for the moment, so we’ll have time to test it until 7.13 release
I'll take it !

[sulemanof]

Closed in #93015