refactor(connector): added amount conversion framework for Gpayments (#4978)

crates/router/tests/connectors/gpayments.rs

@@ -11,7 +11,7 @@ impl utils::Connector for GpaymentsTest {
     fn get_data(&self) -> types::api::ConnectorData {
         use router::connector::Gpayments;
         utils::construct_connector_data_old(
-            Box::new(&Gpayments),
+            Box::new(Gpayments::new()),
             types::Connector::Threedsecureio,
             // Added as Dummy connector as template code is added for future usage
             types::api::GetToken::Connector,