[AP-1794] bug fix for partial sync multiprocessing

[amofakhar]

Context

https://transferwise.atlassian.net/browse/AP-1794

Types of changes

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• Bugfix (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 not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

• I have read the CONTRIBUTING doc
• Description above provides context of the change
• I have added tests that prove my fix is effective or that my feature works
• Unit tests for changes (not needed for documentation changes)
• CI checks pass with my changes
• Branch name starts with AP-NNN (if applicable. AP-NNN = JIRA ID)
• Relevant documentation is updated including usage instructions

Details from ticket: AP-1794

Partial-Sync launches the same sync jobs multiple times as sub-processes

h2. Problem

Partial-Sync launches the same sync jobs multiple times as sub-processes

[https://wise.slack.com/archives/GTAG72L9J/p1721240775328399|https://wise.slack.com/archives/GTAG72L9J/p1721240775328399|smart-link]