benchmark-dockerized.sh: don't redundantly install gotestsum

this is handled centrally by make test which is called by make test-integration which this script calls

only make test's implementation actually calls gotestsum, and it also handles installing if needed

Author: BenTheElder

hack/jenkins/benchmark-dockerized.sh

@@ -48,7 +48,6 @@ if [ -n "${KUBE_HACK_TOOLS_GOTOOLCHAIN:-}" ]; then
   hack_tools_gotoolchain="${KUBE_HACK_TOOLS_GOTOOLCHAIN}";
 fi
 GOTOOLCHAIN="${hack_tools_gotoolchain}" go -C "${KUBE_ROOT}/hack/tools" install github.com/cespare/prettybench
-GOTOOLCHAIN="${hack_tools_gotoolchain}" go -C "${KUBE_ROOT}/hack/tools" install gotest.tools/gotestsum
 
 # Disable the Go race detector.
 export KUBE_RACE=" "