[Discover] Doc viewer does not break extremely long field names, leading to horizontal scrolling

[wylieconlon]

I was testing Discover with the data generated by makelogs and ran into this case where the default doc viewer produces very unexpected results:

The root cause of this is that there is a field named thisisaverylongfieldnamethatevendoesnotcontainanyspaceswhyitcouldpotentiallybreakouruiinseveralplaces in the makelogs data, and field names are styled with white-space: nowrap instead of breaking.

Steps to reproduce

1. Create sample data with a field name that is as long as the example above, or ingest data using makelogs.
2. Open Discover

The behavior I would expect is that Discover should be applying word wrapping on long field names.

[elasticmachine]

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

[kertal]

fixed by #102149