Use keyword arguments for calls to sklearn.metrics functions

[jeremycz]

Use keyword arguments for the following function calls/arguments:

• metrics.fbeta_score - beta
• metrics.classification_report - labels

Passing these as positional arguments will cause an error from sklearn 0.25.

Scikit-learn enhancement proposal SLEP009

[codecov-commenter]

Codecov Report

Merging #51 into master will not change coverage.
The diff coverage is 50.00%.

@@           Coverage Diff           @@
##           master      #51   +/-   ##
=======================================
  Coverage   92.60%   92.60%           
=======================================
  Files           8        8           
  Lines         257      257           
  Branches       37       37           
=======================================
  Hits          238      238           
  Misses         15       15           
  Partials        4        4           

Impacted Files	Coverage Δ
sklearn_crfsuite/metrics.py	94.11% <50.00%> (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 293a2d0...8027bf3. Read the comment docs.