Add cli flag to supply namespace for capi controller to watch for Objects

[DheerajSShetty]

/kind feature
Add cli flag to supply namespace for capi controller to watch for Objects

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[detiber]

Currently we hard code the lister to watch for updates in all Namespaces, We should expose the ability to set a specific namespace using the manager command line arguments that is passed to the lister to limit to a specific namespace.

[vikaschoudhary16]

/assign

[k8s-ci-robot]

@vikaschoudhary16: GitHub didn't allow me to assign the following users: vikaschoudhary16.

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/assign

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[vikaschoudhary16]

@detiber can you please assign this to me, if anyone is not working already.

[vikaschoudhary16]

https://github.com/kubernetes-sigs/controller-runtime/pull/405/files

[detiber]

/assign
/lifecycle active

[detiber]

@vikaschoudhary16 I've assigned it to myself (since it doesn't appear that you are a member of the kubernetes-sigs org), and marked it as active.

If you are already a member of the kubernetes org, you can request to be added to the kubernetes-sigs org as well. If not, I'm also happy to sponsor you for membership in kubernetes-sigs.

[detiber]

@vikaschoudhary16 this shouldn't require any changes to controller-runtime. Here is how we added the support to cluster-api-provider-aws: kubernetes-sigs/cluster-api-provider-aws#607 and kubernetes-sigs/cluster-api-provider-aws#615