Chain exceptions on WorkQueueTaskFailure when a cause is available

[benclifford]

This will add exception chaining when an underlying exception is available, so that reporting of a WorkQueueTaskError will include before the WorkQueueTaskError. This means, in the case of a FileNotFoundError, that the filename that could not be found will now be reported.

 FileNotFoundError: [Errno 2] No such file or directory: '/home/runner/work/parsl/parsl/runinfo/003/WorkQueueExecutor/function_data/0011/result'

parsl/executors/workqueue/executor.py:1059: FileNotFoundError

The above exception was the direct cause of the following exception:

[benclifford]

@dthain maybe you have someone to review this

See issue #2914 for the motivating issue that I am debugging.

[benclifford]

I discussed this with @tphung3 and I think he's ok with me merging it