Publish Docker images tagged as `3.0` for Fabric v3

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As a chaincode developer I want chaincode contained images tagged as 3.0 in Docker Hub So that I can deploy chaincode to Fabric v3 using the default (Docker) chaincode builder

By default, Fabric uses chaincode container images tagged with the same major/minor version number as the Fabric peer. For example, Fabric v3.0.x will look for a hyperledger/fabric-javaenv:3.0 Docker image in Docker Hub.