Add baseline table to output file generated by the tc --sqldb command

[martinholmer]

In prior versions of the Tax-Calculator CLI tool, tc, the --sqldb option created an SQLite3 database that contained variables for the specified reform, but not variables for the baseline. This made it more difficult for users to conduct analysis of policy reforms using SQL scripts.

This pull request enhances the tc tool so that the --sqldb option generates an SQLite3 database that contains two tables (each containing the same set of specified variables), one for the baseline and one for the reform.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (f850d81) 98.54% compared to head (d806ac3) 98.54%.
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2714   +/-   ##
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  Coverage   98.54%   98.54%           
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  Files          14       14           
  Lines        2608     2616    +8     
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+ Hits         2570     2578    +8     
  Misses         38       38           

Flag	Coverage Δ
unittests	98.54% <100.00%> (+<0.01%)	⬆️

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

[jdebacker]

@martinholmer Thanks for making this change.

Can you write a unit test that covers the taxcalcio.analyze function with the new outputs? With that, I think this PR will be ready to merge.

[martinholmer]

@jdebacker, Why am I now getting the following error?
What is the failing test meant to do: Test reading JSON assumption file using URL.

[martinholmer]

@jdebacker, Can you merge #2714?
This PR did pass all the tests on ubuntu,3.9.

[jdebacker]

Thanks @martinholmer. Merging.