fix(docs): fix nginx example chart name
fix(docs): fix nginx example chart name

The name was not correctly truncating, which occasionally resulted
in naming errors, since Kubernetes restricts names to 24 characters.

yan234280533/helm,kdada/helm,flynnduism/helm,michelleN/deployment-manager,jascott1/helm,SlickNik/helm,kdada/helm,jascott1/helm,rbwsam/helm,adamreese/deployment-manager,adamreese/deployment-manager,qwangrepos/helm,helm/helm,iamzhout/helm,yan234280533/helm,michelleN/deployment-manager,fibonacci1729/helm,adamreese/deployment-manager,technosophos/k8s-helm,flynnduism/helm,helm/helm,michelleN/deployment-manager,appscode/helm,adamreese/helm,technosophos/deployment-manager,adamreese/deployment-manager,eicnix/helm,sushilkm/helm,technosophos/deployment-manager,thomastaylor312/helm,thomastaylor312/helm,eicnix/helm,adamreese/helm,qwangrepos/helm,technosophos/deployment-manager,vaikas-google/deployment-manager,sushilkm/helm,rbwsam/helm,technosophos/deployment-manager,SlickNik/helm,FengyunPan/helm,technosophos/k8s-helm,iamzhout/helm,vaikas-google/deployment-manager,appscode/helm,fibonacci1729/helm,adamreese/deployment-manager,technosophos/deployment-manager,FengyunPan/helm,bacongobbler/helm,michelleN/deployment-manager,bradj/helm,bacongobbler/helm,bradj/helm