MySQL/Postgres/CloudMonitoring: Fixes issues related to babel upgrade (#32619)

public/app/plugins/datasource/cloud-monitoring/config_ctrl.ts

@@ -10,9 +10,12 @@ export interface JWT {
 
 export class CloudMonitoringConfigCtrl {
   static templateUrl = 'public/app/plugins/datasource/cloud-monitoring/partials/config.html';
+
+  // Set through angular bindings
+  declare current: any;
+  declare meta: any;
+
   datasourceSrv: DatasourceSrv;
-  current: any;
-  meta: any;
   jsonText: string;
   validationErrors: string[] = [];
   inputDataValid: boolean;

public/app/plugins/datasource/mssql/config_ctrl.ts

@@ -7,7 +7,9 @@ import {
 export class MssqlConfigCtrl {
   static templateUrl = 'partials/config.html';
 
-  current: any;
+  // Set through angular bindings
+  declare current: any;
+
   onPasswordReset: ReturnType<typeof createResetHandler>;
   onPasswordChange: ReturnType<typeof createChangeHandler>;
   showUserCredentials: boolean;

public/app/plugins/datasource/postgres/config_ctrl.ts

@@ -9,7 +9,9 @@ import DatasourceSrv from 'app/features/plugins/datasource_srv';
 export class PostgresConfigCtrl {
   static templateUrl = 'partials/config.html';
 
-  current: any;
+  // Set through angular bindings
+  declare current: any;
+
   datasourceSrv: any;
   showTimescaleDBHelp: boolean;
   onPasswordReset: ReturnType<typeof createResetHandler>;