chore: fix type: set[str] instead of Template

Author: aaronsteers

airbyte_cdk/sources/declarative/interpolation/jinja.py

@@ -120,7 +120,7 @@ def _literal_eval(self, result: Optional[str], valid_types: Optional[Tuple[Type[
     def _eval(self, s: Optional[str], context: Mapping[str, Any]) -> Optional[str]:
         try:
             undeclared = self._find_undeclared_variables(s)
-            undeclared_not_in_context = {var for var in undeclared if var not in context}  # type: ignore [attr-defined]  # `Template` class not iterable
+            undeclared_not_in_context = {var for var in undeclared if var not in context}
             if undeclared_not_in_context:
                 raise ValueError(
                     f"Jinja macro has undeclared variables: {undeclared_not_in_context}. Context: {context}"
@@ -132,12 +132,12 @@ def _eval(self, s: Optional[str], context: Mapping[str, Any]) -> Optional[str]:
             return s
 
     @cache
-    def _find_undeclared_variables(self, s: Optional[str]) -> Template:
+    def _find_undeclared_variables(self, s: Optional[str]) -> set[str]:
         """
         Find undeclared variables and cache them
         """
         ast = self._environment.parse(s)  # type: ignore # parse is able to handle None
-        return meta.find_undeclared_variables(ast)  # type: ignore [return-value]  # Expected `Template` but got `set[str]`
+        return meta.find_undeclared_variables(ast)
 
     @cache
     def _compile(self, s: Optional[str]) -> Template: