🌱 add make targets to build and push vm operator image for testing purposes

[chrischdi]

What this PR does / why we need it:

Usage:

make release-vm-operator

Or to build and push a specific version:

VM_OPERATOR_VERSION=v1.8.1 make release-vm-operator

Outputs:

Multiarch image (linux/amd64, linux/arm64) at: https://gcr.io/k8s-staging-capi-vsphere/extra/vm-operator:v1.8.1

Manifest at: https://storage.googleapis.com/artifacts.k8s-staging-capi-vsphere.appspot.com/vm-operator/v1.8.1.yaml

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 64.01%. Comparing base (180146b) to head (91b4212).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2785   +/-   ##
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  Coverage   64.01%   64.01%           
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  Files         160      160           
  Lines        9345     9345           
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  Hits         5982     5982           
  Misses       2906     2906           
  Partials      457      457           

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[fabriziopandini]

@chrischdi
is it possible to have a single make release-vm-operator target with build, push, and also generate the manifest + upload?

[fabriziopandini]

/lgtm
/approve

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: cfe825d6e7cc906db3556f9c033181971949ca10

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: fabriziopandini

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