chore: backport a pre-delete helm hook for sriov-network-operator

[almaslennikov]

Mutating and Validating webhook configs are created programmatically and are not managed by helm.
To clean them up on helm delete, adding a small pre-delete hook
Backport of: k8snetworkplumbingwg/sriov-network-operator#751

[coveralls]

Pull Request Test Coverage Report for Build 10144483051

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 6 unchanged lines in 3 files lost coverage.
• Overall coverage increased (+0.2%) to 64.977%

---

Files with Coverage Reduction	New Missed Lines	%
controllers/nicclusterpolicy_controller.go	2	79.5%
controllers/hostdevicenetwork_controller.go	2	89.77%
controllers/macvlannetwork_controller.go	2	86.25%

Totals
Change from base Build 10135311110:	0.2%
Covered Lines:	3308
Relevant Lines:	5091

---

💛 - Coveralls

[rollandf]

What happens if these CRs are not available? Will the Job fail?
Do we need ; at the end?
Maybe add || true;

[rollandf]

I think we can close this one.
Covered in k8snetworkplumbingwg/sriov-network-operator#791