Add support to override resource manager

[Karthik-K-N]

/kind feature
/area provider/ibmcloud

Describe the solution you'd like
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A PR has been merged to support overriding possible IBM Cloud service endpoints #1648

But it missed to consider support for overriding ResourceManager :

cluster-api-provider-ibmcloud/cloud/scope/powervs_cluster.go

Line 1701 in 1ca38b0

rmv2, err := resourcemanagerv2.NewResourceManagerV2(&resourcemanagerv2.ResourceManagerV2Options{

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[Karthik-K-N]

/assign

[Amulyam24]

/close

[k8s-ci-robot]

@Amulyam24: Closing this issue.

In response to this:

/close

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