[Lens] Allow inspecting saved objects

[timroes]

Lens currently has no saved object inspector registered, thus if you go to Management > Saved Objects you cannot analyze any Lens saved object. We should register one, so users (and developers) can actually look into the saved objects easily.

Blocked on:

• Inspect view in saved objects management should show read-only JSON #59588
• SavedObjects management section cleanup #62048

[elasticmachine]

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

[flash1293]

Removing the "basic expectation" label as this is not possible for saved objects like Maps as well and wouldn't be a blocker for GA.

[stratoula]

This is done!