Upgrade kustomize to 4.0.4

[jsturtevant]

What type of PR is this?
/kind cleanup

What this PR does / why we need it:
We haven't upgraded kustomize in a while. There was a bug found in #1388 (comment) that didn't serialize integers correctly.

The version bump from 0.3.6 to 0.3.7 broke the way patches are used (https://github.com/kubernetes-sigs/kustomize/releases/tag/kustomize%2Fv3.8.7 and kubernetes-sigs/kustomize#2342)

The docs say:

The name and namespace fields of the patch target selector are automatically anchored regular expressions. This means that the value myapp is equivalent to ^myapp$.

which is why we had to update the patchesJson to use regular expressions vs just the ${CLUSTER_NAME}-md-0.

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 #

Special notes for your reviewer:
I did each upgrade on a separate commit to track the changes required.

Can't go past 4.0.4 because 4.0.5+ introduce a white space break on long linds in yaml.

Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

TODOs:

• squashed commits
• includes documentation
• adds unit tests

Release note:

Upgrade kustomize to 4.0.4

[jsturtevant]

xref: kubernetes-sigs/kustomize#3969 for the white space issue in 4.0.5+

[CecileRobertMichon]

/lgtm
/approve

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