Rename should_call to should_call_spy

[ollipa]

Closes #86

[codecov-commenter]

Codecov Report

Merging #91 (613d230) into master (d9fd8bd) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master      #91   +/-   ##
=======================================
  Coverage   98.05%   98.06%           
=======================================
  Files           4        4           
  Lines         822      826    +4     
=======================================
+ Hits          806      810    +4     
  Misses         16       16           

Impacted Files	Coverage Δ
src/flexmock/_api.py	99.72% <100.00%> (+<0.01%)	⬆️

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[christophe-riolo]

I had doubts about the name still (it's so long), but after thinking about it more I'm fine with it 👍

[ollipa]

@adarshk7, what do you think?

[adarshk7]

Added my thoughts to comment on the original issue 😄

[ollipa]

I think @adarshk7 made some good points. I'll close this PR and let's continue the discussion in #86 issue.