Update CAPI / golangci-lint / go

[cpanato]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

• bump capi to v1.7.2
• update go to 1.21.10
• update golangci-lint rules and fix lints

/assign @damdo @richardcase

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:

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:

- bump capi to v1.7.2 
- update go to 1.21.10 
- update golangci-lint rules and fix lints

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cpanato

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[damdo]

/lgtm