Update config for graceful node shutdown job
Update config for graceful node shutdown job

* Remove explicitly setting `GracefulNodeShutdown` feature gate, since
  it's now enabled by defaulted as a beta feature as of 1.21
* Enable `DynamicKubeletConfig` feature gate, since the test needs to
  update kubelet config at runtime

michelle192837/test-infra,jessfraz/test-infra,cblecker/test-infra,monopole/test-infra,dims/test-infra,cblecker/test-infra,michelle192837/test-infra,cjwagner/test-infra,kubernetes/test-infra,kubernetes/test-infra,cblecker/test-infra,fejta/test-infra,dims/test-infra,cblecker/test-infra,jessfraz/test-infra,kubernetes/test-infra,michelle192837/test-infra,fejta/test-infra,kubernetes/test-infra,BenTheElder/test-infra,michelle192837/test-infra,BenTheElder/test-infra,BenTheElder/test-infra,fejta/test-infra,cjwagner/test-infra,monopole/test-infra,monopole/test-infra,dims/test-infra,fejta/test-infra,cjwagner/test-infra,cjwagner/test-infra,jessfraz/test-infra,michelle192837/test-infra,dims/test-infra,BenTheElder/test-infra,fejta/test-infra,cblecker/test-infra,monopole/test-infra,jessfraz/test-infra,BenTheElder/test-infra,jessfraz/test-infra,cblecker/test-infra,fejta/test-infra,michelle192837/test-infra,dims/test-infra,kubernetes/test-infra,jessfraz/test-infra,dims/test-infra,cjwagner/test-infra,monopole/test-infra,BenTheElder/test-infra,kubernetes/test-infra,monopole/test-infra,cjwagner/test-infra