Remove yyyymmdd_to_datetime function

The functionality of the `yyyymmdd_to_datetime` function
is already contained in the Dates package.

ext/nc_common.jl

@@ -14,25 +14,8 @@ function read_available_dates(ds::NetCDFDataset)
             reinterpret.(Ref(NCDatasets.DateTimeStandard), ds["time"][:])
         )
     elseif "date" in keys(ds.dim)
-        return yyyymmdd_to_datetime.(string.(ds["date"][:]))
+        return Dates.DateTime.(string.(ds["date"][:]), Ref("yyyymmdd"))
     else
         return Dates.DateTime[]
     end
 end
-
-"""
-    strdate_to_datetime(strdate::String)
-
-Convert from String ("YYYYMMDD") to Date format.
-
-# Arguments
-- `yyyymmdd`: [String] to be converted to Date type
-"""
-function yyyymmdd_to_datetime(strdate::String)
-    length(strdate) == 8 || error("$strdate does not have the YYYYMMDD format")
-    return Dates.DateTime(
-        parse(Int, strdate[1:4]),
-        parse(Int, strdate[5:6]),
-        parse(Int, strdate[7:8]),
-    )
-end