Fix bug of label_propagation

[FuJiaJie123]

Fix bug of issue #297 I have read the CLA Document and I hereby sign the CLA

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[!IMPORTANT] Fixes bug in label_propagation() in community_operations.py by updating community assignment logic to consider candidate rank.

• Bug Fix:
  • Fixes bug in label_propagation() in community_operations.py related to community assignment logic.
  • Ensures new_community is updated only if community_candidate is valid and candidate_rank > 1.
• Behavior:
  • Handles cases where community_lst is empty by setting default values (0, -1).

^{This description was created by for 5dba9500fa709719a6179c4fcac93fcce254fb7f. It will automatically update as commits are pushed.}

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[FuJiaJie123]

I have read the CLA Document and I hereby sign the CLA