Improve Behavior parameter validation logic

[martinholmer]

This pull request strengthens the parameter validation logic in the Behavior class, particularly when the Behavior constructor is supplied a dictionary (instead of the usual procedure of reading the default parameters and their values from the behavior.json file).

Note: this pull request extends the changes made in #1554.

@MattHJensen @feenberg @Amy-Xu @andersonfrailey @hdoupe @GoFroggyRun

[codecov-io]

Codecov Report

Merging #1556 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #1556   +/-   ##
======================================
  Coverage     100%    100%           
======================================
  Files          37      37           
  Lines        2603    2644   +41     
======================================
+ Hits         2603    2644   +41

Impacted Files	Coverage Δ
taxcalc/parameters.py	100% <100%> (ø)	⬆️
taxcalc/behavior.py	100% <100%> (ø)	⬆️

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