[Lens] The chart re-renders too often

[cchaos]

Kibana version: Master (post 7.8)

Describe the bug:

When dragging another field after having created a chart, when I hover over the existing chart it turns blank and goes into the loading state just to re-render again.

Expected behavior:

Don't re-render until AFTER having dropped tje field.

Screenshots (if relevant):

[elasticmachine]

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

[mbondyra]

The issue lies here: https://github.com/elastic/kibana/pull/65675/files#diff-e0914c601f0915b0642a0b2a04911ea4R227 - we're passing a callback function that's not memoized and it causes the unnecessary rerender.