clean-up "nolint" comments, remove unused ones

- fix "nolint" comments to be in the correct format (`//nolint:<linters>[,<linter>`
  no leading space, required colon (`:`) and linters.
- remove "nolint" comments for errcheck, which is disabled in our config.
- remove "nolint" comments that were no longer needed (nolintlint).
- where known, add a comment describing why a "nolint" was applied.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

pkg/cri/opts/container.go

@@ -83,7 +83,7 @@ func WithVolumes(volumeMounts map[string]string) containerd.NewContainerOpts {
 		// if it fails but not RM snapshot data.
 		// refer to https://github.com/containerd/containerd/pull/1868
 		// https://github.com/containerd/containerd/pull/1785
-		defer os.Remove(root) // nolint: errcheck
+		defer os.Remove(root)
 
 		unmounter := func(mountPath string) {
 			if uerr := mount.Unmount(mountPath, 0); uerr != nil {