wait for job `clean` event by default in `flux run` and `flux job attach`

[grondo]

This PR is meant to be merged after #5818. It updates the default wait-event for flux job attach to clean from finish. This means that flux run and flux alloc will now wait until a job is fully inactive before exiting. This handles cases where epilog actions perform some work that is expected to be complete before a synchronous job run completes (by exiting).

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 83.35%. Comparing base (687b6a0) to head (483b9ad). Report is 1 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #6065 +/- ## ========================================== - Coverage 83.36% 83.35% -0.01% ========================================== Files 519 519 Lines 83818 83818 ========================================== - Hits 69873 69867 -6 - Misses 13945 13951 +6 ``` | [Files](https://app.codecov.io/gh/flux-framework/flux-core/pull/6065?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=flux-framework) | Coverage Δ | | |---|---|---| | [src/cmd/job/attach.c](https://app.codecov.io/gh/flux-framework/flux-core/pull/6065?src=pr&el=tree&filepath=src%2Fcmd%2Fjob%2Fattach.c&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=flux-framework#diff-c3JjL2NtZC9qb2IvYXR0YWNoLmM=) | `85.83% <100.00%> (+0.16%)` | :arrow_up: | ... and [7 files with indirect coverage changes](https://app.codecov.io/gh/flux-framework/flux-core/pull/6065/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=flux-framework)