auto-merge not working when using with `digger apply -p`

[duy0611]

I have setup my digger with Orchectrator backend and auto_merge: true. When issuing digger apply with -p flag, the PR is merged immediately when digger apply completes even though not all the impacted projects are applied.

Reading in the code, it seems the case has only be addressed in backendless mode (purely with cli), in which we do check if all the impacted projects have been applied before merging the PR. But it is not in case of Orchestrator backend, in which we check only if all the newly created jobs associated with the created batch have been applied successfully.

Reproduce:

• Setup Digger with backend mode
• Add auto_merge: true to digger.yaml file
• Create example repo with at least 2 impacted projects
• Create PR and run digger apply with -p flag

Expected result:

• The mentioned project should be applied successfully, but the PR should not merge yet because not all the impacted projects have been applied

Actual result:

• The PR is merged and other impacted projects are not yet applied

Fix:

• Following is my attempted PR to fix the issue: fix: auto_merge not working properly with orchestrator backend #1871. Warmly welcome if you have any feedback for the issue or my PR.