[Lens] Add telemetry for visualizations failing to load

[flash1293]

To get a better idea about what's causing Lens visualizations fail to load (or which factors contribute to it), we should add some basic UI counters:

• validation error in embeddable
• expression runtime error in embeddable

This can be used to correlate certain things (like heavy usage of runtime fields) with errors during rendering Lens visualizations

[elasticmachine]

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

[flash1293]

Pushing this into 7.14 because this would require too heavy changes at the current place. If possible we should do the telemetry migration before starting to work on this.