Workflows have been refactored so that Celo-related artifacts could be
deployed in the chain of automatic execusions triggered by the manual
dispatch of the `Main` workflow in the `ci` project (with `environment`
set to `alfajores`).

Name of the environment variables for different networks have been
unified to make the migrations more generic.

Inintcontainer image name will now contain a suffix reflecting the chain
for which it is configured. In the future we may add a suffix with
the network name as well.