Nextflow eagerly terminates Azure Batch jobs during execution

[adamrtalbot]

New feature

Based on comment: #3927 (comment)

Azure Batch jobs are terminated during pipeline closing down, see #3927.

During that PR, we discussed eagerly changing the setting of each job to onAllTasksComplete = 'terminate' but never looked further into it.

Use case

The main benefit of doing it this way is that if Nextflow fails to close properly (i.e. is killed), most active jobs will be marked as to be terminated and be removed from the active job quota.

Suggested implementation

We just need an "onProcessClose" event to notify when all tasks are created. I've already added it in a number of PRs, like this one: #3818

The suggestion from the first PR which could be implemented ☝