Update grafana/grafana Docker tag to v7.3.4
Update grafana/grafana Docker tag to v7.3.4

REANNZ/faucet,REANNZ/faucet,shivarammysore/faucet,faucetsdn/faucet,anarkiwi/faucet,anarkiwi/faucet,faucetsdn/faucet,shivarammysore/faucet,mwutzke/faucet,mwutzke/faucet