Update reflect2 to 1.0.1 (memory utilization fix)

Picking up https://github.com/modern-go/reflect2/pull/2 which lazy
initializes a map of all types which we don't use in k8s, saving
memory & initialization time.

vendor/github.com/modern-go/reflect2/test.sh

@@ -3,7 +3,7 @@
 set -e
 echo "" > coverage.txt
 
-for d in $(go list ./... | grep -v vendor); do
+for d in $(go list github.com/modern-go/reflect2-tests/... | grep -v vendor); do
     go test -coverprofile=profile.out -coverpkg=github.com/modern-go/reflect2 $d
     if [ -f profile.out ]; then
         cat profile.out >> coverage.txt