Don't override to_pandas for Datelike columns (#15167)

`pandas.Series(pyarrow.array)` is first interpreted as an object data type since pandas doesn't know how to handle pyarrow arrays yet which is bad. Additionally if pyarrow becomes required in pandas this may have different behavior in the future.

I think the linked issues might be outdated and we can rely on pyarrow's `to_pandas`

Authors:
  - Matthew Roeschke (https://github.com/mroeschke)

Approvers:
  - Ashwin Srinath (https://github.com/shwina)

URL: #15167

python/cudf/cudf/core/column/datetime.py

@@ -313,33 +313,6 @@ def dayofyear(self) -> ColumnBase:
     def day_of_year(self) -> ColumnBase:
         return self.get_dt_field("day_of_year")
 
-    def to_pandas(
-        self,
-        *,
-        index: Optional[pd.Index] = None,
-        nullable: bool = False,
-        arrow_type: bool = False,
-    ) -> pd.Series:
-        if arrow_type and nullable:
-            raise ValueError(
-                f"{arrow_type=} and {nullable=} cannot both be set."
-            )
-        elif nullable:
-            raise NotImplementedError(f"{nullable=} is not implemented.")
-        elif arrow_type:
-            return pd.Series(
-                pd.arrays.ArrowExtensionArray(self.to_arrow()), index=index
-            )
-        else:
-            # `copy=True` workaround until following issue is fixed:
-            # https://issues.apache.org/jira/browse/ARROW-9772
-            return pd.Series(
-                self.to_arrow(),
-                copy=True,
-                dtype=self.dtype,
-                index=index,
-            )
-
     @property
     def values(self):
         """

python/cudf/cudf/core/column/timedelta.py

@@ -146,33 +146,6 @@ def to_arrow(self) -> pa.Array:
             null_count=self.null_count,
         )
 
-    def to_pandas(
-        self,
-        *,
-        index: Optional[pd.Index] = None,
-        nullable: bool = False,
-        arrow_type: bool = False,
-    ) -> pd.Series:
-        # `copy=True` workaround until following issue is fixed:
-        # https://issues.apache.org/jira/browse/ARROW-9772
-        if arrow_type and nullable:
-            raise ValueError(
-                f"{arrow_type=} and {nullable=} cannot both be set."
-            )
-        elif nullable:
-            raise NotImplementedError(f"{nullable=} is not implemented.")
-        elif arrow_type:
-            return pd.Series(
-                pd.arrays.ArrowExtensionArray(self.to_arrow()), index=index
-            )
-        else:
-            return pd.Series(
-                self.to_arrow(),
-                copy=True,
-                dtype=self.dtype,
-                index=index,
-            )
-
     def _binaryop(self, other: ColumnBinaryOperand, op: str) -> ColumnBase:
         reflect, op = self._check_reflected_op(op)
         other = self._wrap_binop_normalization(other)