## What changes were proposed in this pull request?
The expressions `DayWeek`, `DayOfWeek`, `WeekDay` and `WeekOfYear` are changed to use Proleptic Gregorian calendar instead of the hybrid one (Julian+Gregorian). This was achieved by using Java 8 API for date/timestamp manipulation, in particular the `LocalDate` class.
Week of year calculation is performed according to ISO-8601. The first week of a week-based-year is the first Monday-based week of the standard ISO year that has at least 4 days in the new year (see https://docs.oracle.com/javase/8/docs/api/java/time/temporal/IsoFields.html).
## How was this patch tested?
The changes were tested by `DateExpressionsSuite` and `DateFunctionsSuite`.
Closes#23594 from MaxGekk/dayweek-gregorian.
Lead-authored-by: Maxim Gekk <max.gekk@gmail.com>
Co-authored-by: Maxim Gekk <maxim.gekk@databricks.com>
Signed-off-by: Herman van Hovell <hvanhovell@databricks.com>
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