fix: corrected the sync-protocol implementation on next sync committee updates

[srdtrk]

Description

closes: #370

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Before we can merge this PR, please make sure that all the following items have been
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• Linked to GitHub issue with discussion and accepted design, OR link to spec that describes this work.
• Wrote unit and integration tests.
• Added relevant natspec and godoc comments.
• Provide a conventional commit message to follow the repository standards.
• Re-reviewed Files changed in the GitHub PR explorer.
• Review SonarCloud Report in the comment section below once CI passes.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.86%. Comparing base (da3a351) to head (1780588).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #406   +/-   ##
=======================================
  Coverage   99.86%   99.86%           
=======================================
  Files          14       14           
  Lines         740      740           
=======================================
  Hits          739      739           
  Misses          1        1           

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