[APM] Support space-aware index pattern objects

[ogupte]

APM creates a static index pattern as a global saved object (https://github.com/elastic/kibana/blob/master/x-pack/plugins/apm/server/lib/index_pattern/create_static_index_pattern.ts#L37-L44). We should be persisting this as a space-aware saved object instead to conform to other observability plugins and consequently adds support for multiple APM index mappings.

[elasticmachine]

Pinging @elastic/apm-ui (Team:apm)

[ogupte]

This should be considered as part of the existing issue to support setting APM indices in a space-aware context: #49647

[sorenlouv]

While I think this issue was related to #49647 they are different. #49647 only mentions ui indicies while this is for kibana index patterns.

[dgieselaar]

@sqren IIRC, we assumed that this was a miscommunication and the person who asked for it meant UI indices being space-aware.

[kertal]

accidentally added to reference to this issue, sry

[sorenlouv]

we assumed that this was a miscommunication and the person

Sounds good then 👍