refactor: get task job and delete task job

[gaius-qi]

Description

Related Issue

Motivation and Context

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation Update (if none of the other choices apply)

Checklist

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.

[yxxhero]

pls fix ci.

[codecov]

Codecov Report

Attention: Patch coverage is 38.09524% with 13 lines in your changes missing coverage. Please review.

Project coverage is 51.69%. Comparing base (fbb3ee3) to head (39d6723).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
manager/job/task.go	0.00%	12 Missing ⚠️
manager/job/job.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3522      +/-   ##
==========================================
- Coverage   51.72%   51.69%   -0.04%     
==========================================
  Files         190      190              
  Lines       20422    20424       +2     
==========================================
- Hits        10564    10558       -6     
- Misses       9056     9061       +5     
- Partials      802      805       +3     

Flag	Coverage Δ
unittests	51.69% <38.09%> (-0.04%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
pkg/slices/slices.go	100.00% <100.00%> (ø)
manager/job/job.go	0.00% <0.00%> (ø)
manager/job/task.go	0.00% <0.00%> (ø)

... and 3 files with indirect coverage changes

[chlins]

lgtm