message: add test case for election test
diff: @@ -18,6 +18,41 @@ No Issue
  flvt --local-driver -p 5000 --record-size 5000 --spu 2 --replication 2
  ```
  +## Election Scenario
  +
  +Create cluster
  +
  +```
  +fluvio cluster install --spu 3 --local
  +``
  +
  +Create topic with replica 3
  +```
  +fluvio topic create -r 3 topic
  +```
  +
  +Produce message
  +
  +Identity a leader:
  +```
  +fluvio partition list
  +```
  +
  +Read message
  +```
  +fluvio consume topic -B
  +```
  +
  +Kill a leader SPU
  +```
  +ps -ef | grep spu
  +```
  +
  +2nd SPU should take over, this should still work:
  +```
  +flvd consume topic -B
  +```
  +
  