Adding webhook 'delete' command to remove non-namespaced objects

[heyvister1]

sriov-network-operator dynamically creates validating/mutating/clusterroles/clusterrolebinding cluster objects, for specified SriovOperatorConfig. These objects are not being cleaned once sriov operator is uninstalled (via Helm/Openshift).

The proposed PR is to use a small go binary within Helm pre-delete hook. This binary will delete default SriovOperatorConfig, assuming added SriovOperatorConfig finalizer will make sure sriov controller is deleting all generated cluster level objects (e.g. webhooks), prior to operator deployment object is removed by Helm

[github-actions]

Thanks for your PR,
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  Best regards.

[coveralls]

Pull Request Test Coverage Report for Build 11577275447

Details

• 55 of 83 (66.27%) changed or added relevant lines in 3 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.6%) to 45.531%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
controllers/sriovoperatorconfig_controller.go	19	25	76.0%
cmd/sriov-network-operator-config-cleanup/main.go	0	9	0.0%
cmd/sriov-network-operator-config-cleanup/cleanup.go	36	49	73.47%

Files with Coverage Reduction	New Missed Lines	%
controllers/drain_controller.go	1	68.06%

Totals
Change from base Build 11576125023:	0.6%
Covered Lines:	6775
Relevant Lines:	14880

---

💛 - Coveralls

[heyvister1]

/test-all

[adrianchiris]

/test-all

[adrianchiris]

if err is not nil, is it safe to stop the watcher ? or should the defer be moved after the error check ?

[adrianchiris]

overall LGTM, need CI to be green.

added one last comment from my side , thx for the patience ! :)
before we merge please re-work the commits so they do not reflect the review interations but rather the changes done.

e.g

commit 1 : add finalizer to sriovoperatorconfig
commit 2: cleanup binary related changes

[heyvister1]

@zeeke could you please add your approval for this PR?