refactor(test): repost utility deletion flag test

[ruthra-kumar]

Fixes https://github.com/frappe/erpnext/actions/runs/7141720238/job/19450182186?pr=38643#step:13:623

No need to explicitly commit in the repost utility. If there are many vouchers, background job's default timeout is sufficient to handle it. For single doc repost, default request timeout should be fine to repost and commit.

[codecov]

Codecov Report

Merging #38679 (acb6e8e) into develop (9424bbc) will decrease coverage by 0.09%.
Report is 30 commits behind head on develop.
The diff coverage is 16.66%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #38679      +/-   ##
===========================================
- Coverage    60.16%   60.07%   -0.09%     
===========================================
  Files          759      759              
  Lines        69475    69531      +56     
===========================================
- Hits         41800    41774      -26     
- Misses       27675    27757      +82     

Files	Coverage Δ
...post_accounting_ledger/repost_accounting_ledger.py	62.50% <100.00%> (-27.59%)	⬇️
erpnext/accounts/doctype/pricing_rule/utils.py	74.82% <0.00%> (-0.91%)	⬇️

... and 14 files with indirect coverage changes