[release-1.12] 🌱 Fix web-hook structure names and descriptions

[dmvolod]

What this PR does / why we need it:
This is manual backport of the #3462 to release-1.12

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 #

[dmvolod]

/assign @sbueringer

[k8s-ci-robot]

@dmvolod: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-cluster-api-provider-vsphere-apidiff-release-1-12	532bfc3	link	false	/test pull-cluster-api-provider-vsphere-apidiff-release-1-12

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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[sbueringer]

Thx!

/lgtm
/approve

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: f4cbf5b861653931e60e826cc0e49b960cd589f8

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: sbueringer

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