remove restart-kubelet flag.

This flag was added to the test suite in
kubernetes/kubernetes#97028

However as it turns out, in order to test the exit on lock contention,
it is not needed, hence removing the flag from the test job.

Signed-off-by: Imran Pochi <imran@kinvolk.io>

config/jobs/kubernetes/sig-node/node-kubelet.yaml

@@ -408,7 +408,7 @@ periodics:
           - --node-test-args=--kubelet-flags="--exit-on-lock-contention --lock-file=/var/run/kubelet.lock"
           - --node-tests=true
           - --provider=gce
-          - --test_args=--nodes=1 --focus="\[NodeFeature:LockContention\]" --restart-kubelet=false
+          - --test_args=--nodes=1 --focus="\[NodeFeature:LockContention\]"
         env:
           - name: GOPATH
             value: /go