Use rolling window for translating 2-digit years into 4-digit years

[highfalutin]

Overview

Fix outdated hard-coded import logic: translate 2-digit years to 4 using rolling -95yr to +5yr window

Before

1/1/22 is imported as 1922-01-01

After

1/1/22 is imported as 2022-01-01

and, if this code is still running in 2096, 1/1/1 will be imported at 2101-01-01

Comments

See https://lab.civicrm.org/dev/core/-/issues/3037#note_68816

[civibot]

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[colemanw]

@highfalutin can you try out #22580 - if that works for you then it's a better long-term solution.

[colemanw]

@highfalutin can you please squash these 3 commits down to 1?

[highfalutin]

@colemanw done

[eileenmcnaughton]

@colemanw this is mergeable isn't it?

[eileenmcnaughton]

Actually @seamuslee001 @colemanw we should possibly backport this - it seems the existence of 2022 is a regression - which makes sense.

[colemanw]

I'm not sure we can backport this to the year 2020, and I don't think I want to relive that year again either 😝