Remove no longer needed gather_admission_webhooks script

[nekop]

In 4.10, the webhooks info gathered by a part of kube-apiserver co.

$ oc version
Client Version: 4.10.22
Server Version: 4.10.22
Kubernetes Version: v1.23.5+3afdacb

$ oc get co kube-apiserver -o yaml
  - group: admissionregistration.k8s.io
    name: ""
    resource: mutatingwebhookconfigurations
  - group: admissionregistration.k8s.io
    name: ""
    resource: validatingwebhookconfigurations
$ ls ./must-gather/cluster-scoped-resources/admissionregistration.k8s.io/
mutatingwebhookconfigurations  validatingwebhookconfigurations
$ ls ./must-gather/web_hooks/
mutatingwebhookconfigurations.yaml  validatingwebhookconfigurations.yaml # duplicated info

[openshift-bot]

Issues go stale after 90d of inactivity.

Mark the issue as fresh by commenting /remove-lifecycle stale. Stale issues rot after an additional 30d of inactivity and eventually close. Exclude this issue from closing by commenting /lifecycle frozen.

If this issue is safe to close now please do so with /close.

/lifecycle stale

[sferich888]

@nekop we would/will need to backport this to 4.10 correct? cc: @deads2k @sttts (is this ok to remove; and backport)?

[sferich888]

/remove-lifecycle stale

[nekop]

As this is a minor change, I have no backport preference. Latest only fix would be fine for me.

[sferich888]

/lgtm

[openshift-ci[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: nekop, RickJWagner, sferich888

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Needs approval from an approver in each of these files: - ~~[collection-scripts/OWNERS](https://github.com/openshift/must-gather/blob/master/collection-scripts/OWNERS)~~ [RickJWagner,sferich888] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment

[openshift-ci-robot]

/retest-required

Remaining retests: 0 against base HEAD 107f2e049c93f11af986b0b79d5c55a7ecbd5512 and 2 for PR HEAD ce848abc153c7595da4fc7e6b15edc5644a88242 in total

[openshift-ci[bot]]

@nekop: all tests passed!

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