[FIX] evaluation: Fix the method to compute scores

[nicomacr]

Fix to compute score when the max score of a question are zero.

[codecov-io]

Codecov Report

Merging #17 into 11.0 will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##             11.0      #17   +/-   ##
=======================================
  Coverage   49.39%   49.39%           
=======================================
  Files          17       17           
  Lines         330      330           
=======================================
  Hits          163      163           
  Misses        167      167

Impacted Files	Coverage Δ
evaluation/models/survey_user_input.py	19.23% <0%> (ø)	⬆️

---

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 a4f322c...18f93ab. Read the comment docs.

[coveralls]

Coverage remained the same at 49.394% when pulling 18f93ab on adhoc-dev:11.0-h-21624-nmr into a4f322c on ingadhoc:11.0.