[release-0.16] 🌱 Rebase upstream

[samuelvl]

Update release-0.16 branch with last changes from upstream release-0.16 branch:

$ git diff upstream/release-0.16 HEAD
diff --git a/pkg/client/options.go b/pkg/client/options.go
index d81bf25d..ee6489b7 100644
--- a/pkg/client/options.go
+++ b/pkg/client/options.go
@@ -514,7 +514,8 @@ type MatchingLabels map[string]string
 func (m MatchingLabels) ApplyToList(opts *ListOptions) {
        // TODO(directxman12): can we avoid reserializing this over and over?
        if opts.LabelSelector == nil {
-               opts.LabelSelector = labels.NewSelector()
+               opts.LabelSelector = labels.SelectorFromValidatedSet(map[string]string(m))
+               return
        }
        // If there's already a selector, we need to AND the two together.
        noValidSel := labels.SelectorFromValidatedSet(map[string]string(m))

We need this fork because the perf issue fixed in kubernetes-sigs#2529 was not backported to the release-0.16 banch.

[samuelvl]

Closing since kubernetes-sigs#2529 has been backported to the release-0.16 banch.