bootstrap cli: allow dealing with flux namespaces otherthan flux system

[waleedhammam]

followup on #3371 (comment)

AC

• we can bootstrap flux and weave gitops in a namespace different than flux-system where both ns are the same for example weave-gitops

[waleedhammam]

Closing as it's not doable to use another namespace as it's hard-coded in flux/wge, could cause unintended behavior
Also PR became obsolete