Update the golangci-lint tool used in the cert-manager-operator repo to version 2.

• Update the `.golangci.yaml` to indicate version 2
• Update the Makefile lint target to use `github.com/golangci/golangci-lint/v2/cmd/golangci-lint`
• Update the tools/tool.go to import only `github.com/golangci/golangci-lint/v2/cmd/golangci-lint` and remove older version.
• Update the go modules to use `v2.6.2` and vendor the new packages

Acceptance Criteria:

• Create jira story with all the reported the issues by the new linter.