Backtrack on non-finite deviance values

[andreasnoack]

The current criterion for backtracking assumes that the deviance computed is finite. Hence, extreme parameter values can cause termination instead of reduction of the step.

Fixes #417

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.33%. Comparing base (f6f4f70) to head (9e1729c).
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #577      +/-   ##
==========================================
+ Coverage   89.95%   90.33%   +0.37%     
==========================================
  Files           8        8              
  Lines        1105     1107       +2     
==========================================
+ Hits          994     1000       +6     
+ Misses        111      107       -4     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

---

🚨 Try these New Features:

• Flaky Tests Detection - Detect and resolve failed and flaky tests