fix(ci): report lint problems, auto-update dependencies, etc.

[programmer04]

What this PR does / why we need it:

This issue includes a handful of fixes related to the CI:

• add bumping with dependabot for Go dependencies (deliberately left golang.stackrox.io/kube-linter v0.4.0 when v0.6.0 is available to wait for Depndabot)
• remove .github/workflows/lint.yaml that has never been used, see - https://github.com/Kong/charts/actions/workflows/lint.yaml
• bump Go to 1.21 and set Go version based on go.mod instead of hardcoding in CI
• remove the explicit cache for Go dependencies, it's not needed anymore for setup-go v4.0.0
• add bin dir to .gitignore it's a place where kubebuilder is downloaded to
• fix the target for lining scripts, before the change it hasn't propagated the error code, see
  • before
  • after
  • after the fix of the reported problem