Update MANIFEST.in

Include compiled translation (.mo) files in PyPI distributions

## Summary
This MR modifies `MANIFEST.in` to ensure compiled translation (.mo) files are included in PyPI package distributions. 

## Changes
1. Added explicit inclusion pattern for `.mo` files in `MANIFEST.in`

Author: yumendy

MANIFEST.in

@@ -10,7 +10,7 @@ recursive-include extra/*
 recursive-include examples *
 recursive-include requirements *.txt *.rst
 recursive-include t *.py
-recursive-include django_celery_results *.py *.po
+recursive-include django_celery_results *.py *.po *.mo
 
 recursive-exclude * __pycache__
 recursive-exclude * *.py[co]