fix: correctly handle year increment for January dates (Broxbourne Council)

[teofanis]

I've missed this in my previous PR.

The council's dates are provided in day/month format, and the script was incrementing the year if the current month was January. This worked fine for December or November but caused issues when viewing dates in January.

I've updated the script to increment the year for January dates only when parsed in a month other than January.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.93%. Comparing base (2554e6e) to head (0bef678).
Report is 26 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1119   +/-   ##
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  Coverage   71.93%   71.93%           
=======================================
  Files           9        9           
  Lines        1037     1037           
=======================================
  Hits          746      746           
  Misses        291      291           

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