A few minor changes to make input data testing easier

[martinholmer]

This pull request contains a few changes that will make it easier to conduct validation tests of new datasets being developed for use by Tax-Calculator. These changes have no effect on the taxes calculated by the model.

• In the Makefile change the logic of the clean target to correspond to the existing logic in the package target.

• In the Makefile add the --disable-warnings option to just the pytest-cps target.

• Add a SS_all_in_agi boolean parameter to the policy_current_law.json file and use it in the SSBenefits function in the calcfunctions.py module. This parameter permits the estimation of the tax expenditure associated with the less-than-complete taxation of social security benefits.

• Promote a local variable in the GainsTax function in the calcfunctions.py module to be a global variable defined in the records_variables.json file. This variable makes it easier to check that the existing CG_nodiff parameter is doing what it is designed to do.

• Suppress a pandas deprecation warning in the taxcalcio.py module.

• Break up several overly long lines in the pytest_sessionfinish function in the conftest.py module.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (552b2f8) 98.54% compared to head (fe2ff9a) 98.54%.
Report is 1 commits behind head on master.

Additional details and impacted files

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Flag	Coverage Δ
unittests	98.54% <100.00%> (ø)

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Files	Coverage Δ
taxcalc/taxcalcio.py	100.00% <100.00%> (ø)

[jdebacker]

Thanks for this PR @martinholmer! Merging.