feat: Test the database connection of the ExeSQL operator #1739 (#2036)

### What problem does this PR solve?

feat: Test the database connection of the ExeSQL operator #1739
### Type of change


- [x] New Feature (non-breaking change which adds functionality)

web/src/services/flow-service.ts

@@ -10,6 +10,7 @@ const {
   removeCanvas,
   runCanvas,
   listTemplates,
+  testDbConnect,
 } = api;
 
 const methods = {
@@ -41,6 +42,10 @@ const methods = {
     url: listTemplates,
     method: 'get',
   },
+  testDbConnect: {
+    url: testDbConnect,
+    method: 'post',
+  },
 } as const;
 
 const chatService = registerServer<keyof typeof methods>(methods, request);