[Security Solution][Maps] Network Map displays setup instructions when space privileges are set to 'None' for the Maps app

[spong]

Kibana version: 7.9

When Space privileges are set to None for the Maps app, the Network Map will display its default empty view as if it still needs index patterns instead of messaging the user to contact their Kibana Administrator to enable support for Maps.

Ideally, this message/container should be dismissible (and persisted to local storage ala #68372) so that users aren't forced to see an empty container they can't do anything about every time they visit the Network page.

Empty view container as if it can be configured:

cc @mrebeschini @EthanStrider

[elasticmachine]

Pinging @elastic/siem (Team:SIEM)

[elasticmachine]

Pinging @elastic/kibana-security (Team:Security Solution)