How to skip concurrent executions without failing the job

I've got a minutely recurring job that uses `DisableConcurrentExecution(timeout:0)` (0 retries), as only one worker should be processing it at a given time, specially if the job takes more than a minute to complete (it varies).

I don't want the "skipped" jobs to be flagged as `failed` on the dashboard, so I wanted to add a `SkipConcurrentExecutionAttribute` that would be almost identical to `DisableConcurrentExecutionAttribute`, except that it would try/catch around the lock acquisition, and swallow `DistributedLockTimeoutException` and set the job to `DeletedState` with the reason why.

But I can't do this properly, because [GetResource()](https://github.com/HangfireIO/Hangfire/blob/master/src/Hangfire.Core/DisableConcurrentExecutionAttribute.cs#L55) is private, and its implementation refers to other methods that are internal to the library.
`$"{job.Type.ToGenericTypeString()}.{job.Method.Name}"` seems to be the safe way of producing non-conflicting distributed lock names, but I can't refer to it.
Can we have in the lib a public method that generates the job's distributed lock name?

cf., https://discuss.hangfire.io/t/disableconcurentexecution-for-job-groups/1389/4

Start by reading src/Hangfire.Core/DisableConcurrentExecutionAttribute.cs, especially GetResource() and the internal methods it uses to form the distributed lock name. Check how the public API could expose that naming logic for a custom SkipConcurrentExecutionAttribute without relying on private or internal members. Done means the lock name can be generated without conflicting with existing DisableConcurrentExecution behavior.

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