Refactored the Executor interface yet again

[yihuaf]

I apologize having to refactor this interface yet again. Previously, we introduced the executor to be a function pointer. This works out nicely because the function pointer in rust can be clone-ed without hassel. However, I realized that using function pointer is way too restrictive for our users. The executor may wish to include additional context when calling the exec function. The function pointer limited the input only oci spec. The new constraint is that the struct implementing executor must be clone-able, which we need to carry this struct across process boundry.

[codecov-commenter]

Codecov Report

Merging #2230 (009eae7) into main (0fc4c87) will decrease coverage by 0.03%.
Report is 16 commits behind head on main.
The diff coverage is 6.66%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2230      +/-   ##
==========================================
- Coverage   65.03%   65.01%   -0.03%     
==========================================
  Files         129      129              
  Lines       15139    15149      +10     
==========================================
+ Hits         9846     9849       +3     
- Misses       5293     5300       +7     

[YJDoc2]

looks good 👍
I'm going to squash and merge so that the doc test and spell fixing commits get merged together.
If I'm not wrong, then this is basically the original executor scheme except for the executor manager and executor lists, right?

[yihuaf]

If I'm not wrong, then this is basically the original executor scheme except for the executor manager and executor lists, right?

Yes. I also removed the can_handle and the executor name. The executor name is removed because this doesn't apply to the new scheme. The can_handle part of the logic is moved into exec with an error kind can't handle. With that being said, there are some talks to add the can_handle or a validate function back, so we can abstract the validation part of the logic out for each executor.