DOC: add missing parameters to offsets classes: BYearBegin, YearEnd, YearBegin
xref  #52431
Updated documentation for offsets classes. Added missing parameters, See Also section, and examples to `BYearBegin`, `YearEnd`, and `YearBegin`. Corrected the default value for `month` in the class `BYearEnd`.

@MarcoGorelli, could you please take a look at this pr?