Update Product.ts

forgot to change variable name.

src/typeDefs/Product.ts

@@ -46,7 +46,7 @@ const typeDefs = gql`
 
   type Mutation {
     createProduct(input: ProductInput!): Product
-    updateProduct(id: ID!, input: ProductInput!): Product
+    updateProduct(id: ID!, input: UpdateProductInput!): Product
     deleteProduct(id: ID!): Boolean
   }
 `;