Label the production namespaces with active and standby

[seanhamlin]

In order to aid visibility into the stack, it would be nice if the operator could label the 2 production namespaces to indicate which is active and which is now standby.

e.g.

lagoon.sh/active-standby=<acitve|standy>

Cross post from amazeeio/dioscuri#23

[tobybellwood]

going to leave this in dioscuri for action

[shreddedbacon]

With uselagoon/lagoon#3592 we can maybe handle this in Lagoon, or more specifically, the remote-controller. The task has no permission to label namespaces, but on task completion, the remote-controller could add these labels.