ci: Split deploy-gcp-tests workflow into multiple categories

[gustavovalverde]

Motivation

We might get into scenarios were we'd like to disable specific CI tests categories, for example:

• lightwalletd syncs
• zebra syncs OR
• syncs with cached state
• syncs without cached state

As of know, a single workflow is also harder to understand as it has multiple dependencies and relations

Designs

This would require to have at least 2 reusable workflows, which would also simplify the actual dependency tree and allow us to disable specific pieces of the whole Deploy GCP tests :

• deploy-gcp-tests-lwd.yml
• deploy-gcp-tests-zebra.yml