Initialize execution Manager in Report Assembler

[stonezdj]

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

Please indicate you've done the following:

• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 66.34%. Comparing base (b7b8847) to head (23b5a2c).
Report is 190 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #20437      +/-   ##
==========================================
- Coverage   67.56%   66.34%   -1.22%     
==========================================
  Files         991     1042      +51     
  Lines      109181   113165    +3984     
  Branches     2719     2830     +111     
==========================================
+ Hits        73768    75082    +1314     
- Misses      31449    34020    +2571     
- Partials     3964     4063      +99     

Flag	Coverage Δ
unittests	66.34% <0.00%> (-1.22%)	⬇️

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

Files	Coverage Δ
src/server/v2.0/handler/assembler/report.go	71.42% <0.00%> (ø)

... and 567 files with indirect coverage changes

[wy65701436]

lgtm