fix non-full buffers not being written into disk

[nikolay327]

Non-full table buffers in the raw_mgdo.py are currently not being written into disk.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 44.75%. Comparing base (1f400a6) to head (871245c).
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main       #4      +/-   ##
==========================================
+ Coverage   44.67%   44.75%   +0.07%     
==========================================
  Files          18       18              
  Lines        1137     1135       -2     
==========================================
  Hits          508      508              
+ Misses        629      627       -2     

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