Setup Ethereum devnet for GHA

[jpcenteno]

Issue: #68

[jpcenteno]

Note for Monday self:

• I just modified the main branch permissions for this repo (Because I fucked up by pushing to main When I intended to push into another branch).
• Now, the CI pipeline, which is what I'm testing here, is not running.
• Maybe I broke something, maybe it's a problem on the GitHub side. IDK

[jpcenteno]

I got confused because I wasn't getting even a ❌ sign on the left of the commit. It looks that we can see the error log on the actions tab.

The message was:

[Invalid workflow file: .github/workflows/elixir_ci.yml#L27](https://github.com/lambdaclass/ethereum_war_game_tooling/actions/runs/2361011766/workflow)

The workflow is not valid. .github/workflows/elixir_ci.yml (Line: 27, Col: 9): Unexpected value 'command' .github/workflows/elixir_ci.yml (Line: 35, Col: 9): Unexpected value 'hostname'