allow passing private key and bypassing web ui for graph publish

[saihaj]

In #1670 introduce a new command that allows publishing to the network. It links user to go to the cli.thegraph.com (located here) and the user adds metadata and finishes signing in their wallet.

@schmidsi suggested that we should allow user filling out all this metadata via the CLI and then let them provide a local private key which will be used to sign the transaction.

[schmidsi]

Maybe using this: https://github.com/smartcontractkit/env-enc

[mitchhs12]

I think that this should definitely be added. There are many developers that I think would strongly benefit by being able to automate publishing of their deployments.

[schmidsi]

@saihaj any update on this?