Ensure golangci-lint runs on all files

[gibizer]

• removed unused func params
• ignore revive dot-imports rule on ginkgo and gomega as dot import there is the recommended practice
• added missing error handling
• various small style fixes found by the linter

[openshift-ci[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: gibizer, stuggi

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