Inconsistent date literal on line 78 will cause script maintenance issues in the future

[DarrenWHenderson]

CTSA-Metrics/InformaticsMetricACTSQLServer.sql

Line 78 in 17e9243

FROM OBSERVATION_FACT OBS WHERE CONVERT(DATE,OBS.START_DATE) BETWEEN CAST('2020/01/01' AS DATE) AND CAST('12-31-2020' AS DATE)

The date literal '2020/01/01' on line 78 is the only time the floor for the one-year census period is written in yyyy/mm/dd format in the entire script. It will make find-replace in future maintenance of the script fail.