fix: Mapped datetime values are now typed as date-time strings in t…

…he schema message (#2665)

* check for date and datetime in stream_maps

* expr.endswith(".date()")

* Update mapper.py

---------

Co-authored-by: Greg Koutsimpogiorgos <greg.koutsimpogiorgos@mylighthouse.com>
Co-authored-by: Edgar Ramírez Mondragón <16805946+edgarrmondragon@users.noreply.github.com>

singer_sdk/mapper.py

@@ -359,7 +359,7 @@ def _eval(
 
         return result
 
-    def _eval_type(
+    def _eval_type(  # noqa: PLR0911
         self,
         expr: str,
         default: th.JSONTypeHelper | None = None,
@@ -398,6 +398,12 @@ def _eval_type(
         if expr.startswith("bool("):
             return th.BooleanType()
 
+        if expr.startswith("datetime.date") or expr.endswith(".date()"):
+            return th.DateType()
+
+        if expr.startswith("datetime.datetime"):
+            return th.DateTimeType()
+
         return th.StringType() if expr[0] == "'" and expr[-1] == "'" else default
 
     def _init_functions_and_schema(  # noqa: PLR0912, PLR0915, C901