Authentication of new k8s users via serviceaccount with RBAC role

1. Configure RBAC on your cluster (pass –authorization-mode=RBAC to kube-apiserver)
2. Log via ssh in any Linux machine, install kubectl and jq
   ssh vm1 apt update; apt -y install jq curl -LO https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectl chmod +x kubectl mv kubectl /usr/local/bin
3. Create kubeconfig with admin rights, test it
   mkdir ~/.kube
   vim ~/.kube/config
   config
   kubectl get no
4. create adduser.sh file
   adduser.sh
   chmod +x adduser.sh
5. Modify or cut out last section of adduser.sh - part with Role and Rolebinding yaml
6. Execute script, create Role and RoleBinding for new user
   adduser.sh cooluser kubectl create -f role.yaml kubectl create -f cooluser_role_bond.yaml
   sample role sample binding