[Northamptonshire] restrict title to 120 characters

[struan]

Prevent people from using very long titles.

Fixes mysociety/fixmystreet-commercial#1344

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[codecov]

Codecov Report

Merging #2451 into master will increase coverage by <.01%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master    #2451      +/-   ##
==========================================
+ Coverage   81.06%   81.07%   +<.01%     
==========================================
  Files         196      196              
  Lines       12639    12642       +3     
  Branches     2349     2350       +1     
==========================================
+ Hits        10246    10249       +3     
+ Misses       1604     1603       -1     
- Partials      789      790       +1

Impacted Files	Coverage Δ
perllib/FixMyStreet/Cobrand/Northamptonshire.pm	17.5% <66.66%> (+6.68%)	⬆️

---

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[codecov]

Codecov Report

Merging #2451 into master will increase coverage by <.01%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master    #2451      +/-   ##
==========================================
+ Coverage   81.18%   81.18%   +<.01%     
==========================================
  Files         197      197              
  Lines       12632    12635       +3     
  Branches     2344     2345       +1     
==========================================
+ Hits        10255    10258       +3     
+ Misses       1594     1593       -1     
- Partials      783      784       +1

Impacted Files	Coverage Δ
perllib/FixMyStreet/Cobrand/Northamptonshire.pm	17.5% <66.66%> (+6.68%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 15c5006...355f891. Read the comment docs.

[dracos]

Comma issue; could we put maxlength on the actual input to save the user only finding out it's too long when they hit a button? (In fact, maxlength is on textarea too, so we should do this on detail too!)

[dracos]

This is fine; ideally the maxlength should be output in the HTML also if someone has come to /report/new directly (the server presumably can know the location + body at that point, or at least only on the cobrand always would be simpler presumably).