Add growfactors file for a current policy baseline

[jdebacker]

This PR adds a growth factors file for use when using a current policy (i.e., TCJA permanence) baseline.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.42%. Comparing base (1b696b4) to head (c69bd14).

Additional details and impacted files

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  Lines        2610     2610           
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[martinholmer]

@jdebacker said:

This PR adds a growth factors file for use when using a current policy (i.e., TCJA permanence) baseline.

This doesn't make sense to me (neither does the title).

Current-law policy calls for the end of many TCJA provisions.

It is a reform that would extend those provision after 2025.