Remove type check for Dataset class

Fixes #157

Author: nikhilwoodruff

changelog_entry.yaml

@@ -0,0 +1,4 @@
+- bump: patch
+  changes:
+    fixed:
+    - Removed bad type check.

policyengine/simulation.py

@@ -37,7 +37,7 @@
 CountryType = Literal["uk", "us"]
 ScopeType = Literal["household", "macro"]
 DataType = (
-    str | dict[Any, Any] | Dataset | None
+    str | dict[Any, Any] | Any | None
 )  # Needs stricter typing. Any==policyengine_core.data.Dataset, but pydantic refuses for some reason.
 TimePeriodType = int
 ReformType = ParametricReform | Type[StructuralReform] | None