bazel: statically link dockerized components

and remove libc from docker images when it's not needed.

cmd/kubectl/BUILD

@@ -10,6 +10,12 @@ load(
 
 go_binary(
     name = "kubectl",
+    gc_linkopts = [
+        "-linkmode",
+        "external",
+        "-extldflags",
+        "-static",
+    ],
     library = ":go_default_library",
     linkstamp = "k8s.io/kubernetes/pkg/version",
     tags = ["automanaged"],