Improves null check in context hook

Author: Ruben van Leeuwen

frontend/packages/pydantic-forms/src/core/hooks/usePydanticFormContext.tsx

@@ -5,7 +5,7 @@ import { PydanticFormContext } from '@/core/PydanticFormContextProvider';
 export function usePydanticFormContext() {
     const context = useContext(PydanticFormContext);
 
-    if (!context) {
+    if (context === null || context === undefined) {
         throw new Error(
             'usePydanticFormContext must be used within a PydanticFormProvider',
         );