fix: wrap schedule/exec/task creation as orm tx

[chlins]

Wrap orm tx when the scheduler try to create the task because submit job maybe failure depends on the jobservice.

Fixes: #18452

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Comprehensive Summary of your change

Issue being fixed

Fixes #18452

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[codecov]

Codecov Report

Merging #18458 (cc50dde) into main (02c51c6) will increase coverage by 0.00%.
The diff coverage is 66.66%.

@@           Coverage Diff           @@
##             main   #18458   +/-   ##
=======================================
  Coverage   67.36%   67.37%           
=======================================
  Files         982      982           
  Lines      106848   106856    +8     
  Branches     2670     2670           
=======================================
+ Hits        71979    71995   +16     
+ Misses      31000    30990   -10     
- Partials     3869     3871    +2     

Flag	Coverage Δ
unittests	67.37% <66.66%> (+<0.01%)	⬆️

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

Impacted Files	Coverage Δ
src/pkg/scheduler/scheduler.go	66.84% <62.96%> (-0.38%)	⬇️
src/controller/systemartifact/execution.go	72.82% <73.33%> (+0.29%)	⬆️

... and 5 files with indirect coverage changes

[wy65701436]

lgtm