doc: Fix Eventing State doc formatting

[muralov]

Description

Fix eventing state doc formatting

Related issue(s)
#328

[NHingerl]

In line 89, "Impact on Event Flow" must be in title case because it's a heading.

[NHingerl]

In general, how about the following order of rows and columns:

Suggested change

	| Backend Type | Backend Config | Backend State | Eventing State | Impact on Event Flow |
	|----------------|----------------|---------------------------------------------------------------------------------------------------------------------------------------------|----------------|------------------------------------------|
	| NATS/EventMesh | missing | n/a | Warning | No events will be accepted or dispatched |
	| NATS/EventMesh | exists | Processing (mainly happens during initialization and backend switching) | Processing | No events will be accepted or dispatched |
	| NATS | exists | Warning (NATS deletion blocked) | Ready | Events will be accepted or dispatched |
	| NATS | exists | Error (NATS ist unavailable or cannot be connected) | Warning | No events will be accepted or dispatched |
	| NATS | exists | Missing | Warning | No events will be accepted or dispatched |
	| EventMesh | exists | Error (secret for EventMesh missing) | Warning | No events will be accepted or dispatched |
	| NATS/EventMesh | exists | Error (cases not caused by a user, such as cannot create EPP deployment or cannot start subscription manager although backend is available) | Error | No events will be accepted or dispatched |

[muralov]

We discussed the order with Korbinian and we agreed to this order. Why do you want to change it?

[NHingerl]

Because I think a) backend missing or existing is the first important distinction; with a missing backend, all later steps are irrelevant. That's why I pulled that row up. I also added "n/a" to that field, so that there's no misunderstanding whether we simply forgot to enter information there.

Furthermore, because as a user, I think it's easiest to know whether I have NATS or EventMesh, so I pulled that column to the first position.
This also matches the fact that this is about the impact of the backend to the Eventing CR State and Event Flow; so the focus is on the backend. Conversely, if the purpose of the table had been "Understanding the causes of the Eventing state"; I'd pull the "Eventing State" column to the first position.

In general, I personally find option A easier to understand than option B:

Option A

Option B