fix: SubPart commit modified to work when updating an existing subpart

[echambla]

Description

Create a sub part, in a project root part.
Commit.
Modify its axis system.
Commit.
The axis system of the subpart was not modified on the server side.

Issue linked

#639

Checklist

• I have tested my changes locally.
• I have added necessary documentation or updated existing documentation.
• I have followed the coding style guidelines of this project.
• I have added appropriate tests (unit, integration, system).
• I have reviewed my changes before submitting this pull request.
• I have linked the issue or issues that are solved by the PR if any.
• I have assigned this PR to myself.
• I have made sure that the title of my PR follows Conventional commits style (e.g. feat: add optical property)
• I have agreed with the Contributor License Agreement (CLA).

[echambla]

Still need to add unit tests on this.
Not ready for merge

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.91%. Comparing base (689d751) to head (bc874f9).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #664   +/-   ##
=======================================
  Coverage   88.90%   88.91%           
=======================================
  Files          39       39           
  Lines        5616     5618    +2     
=======================================
+ Hits         4993     4995    +2     
  Misses        623      623           

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