Redesign CLI for DR to not take cluster name when not required

[posriniv]

New commands

./ybm dr create --source-cluster-name brilliant-partridge --dr-name first-dr --target-cluster-name passionate-coyote  --databases test1
./ybm dr list
./ybm dr describe --dr-name first-dr
./ybm dr delete --dr-name first-dr
./ybm dr update --dr-name sample-config --databases test1,test2
./ybm dr switchover --dr-name sample-config
./ybm dr failover --dr-name sample-config-final-srinivas --safetimes test1=1729716937,test2=1729716937
./ybm dr restart --dr-name sample-config-final-srinivas --databases test1,test2
./ybm dr pause --dr-name sample-config-final-srinivas --duration 5
./ybm dr resume --dr-name sample-config-final-srinivas