[`hydrate-orchestrator`] Update `GenerateDeployment` function to also check for the `AUTO_MERGE` file and automerge the PR when it exists

[juanjosevazquezgil]

Motivation

Currently, the RunDispatch function calls GenerateKubernetesDeployment and checks for the existence of the AUTO_MERGE file. This means that when a deployment is dispatched, the resulting PR will be automerged if AUTO_MERGE exists. We want this functionality to apply to manual deployments too, and those use the GenerateDeployment function. So we want to also check for the existence of the AUTO_MERGE file within that function too

Acceptance criteria

• The GenerateDeployment function checks for the existance of the AUTO_MERGE file and automerges the PR when it exists