Make all useage of sort deterministic

Lots of places used sort (or sort -u) but didn't set LC_ALL=C. This
means it could be slightly different on different people's systems. Make
it deterministic.

hack/make-rules/test-integration.sh

@@ -43,8 +43,7 @@ kube::test::find_integration_test_dirs() {
     cd ${KUBE_ROOT}
     find test/integration/${1-} -name '*_test.go' -print0 \
       | xargs -0n1 dirname \
-      | uniq \
-      | sort -u
+      | LC_ALL=C sort -u
   )
 }