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/utils/api.ts

@@ -94,4 +94,5 @@ export default {
   setCanvas: `${api_host}/canvas/set`,
   resetCanvas: `${api_host}/canvas/reset`,
   runCanvas: `${api_host}/canvas/completion`,
+  testDbConnect: `${api_host}/canvas/test_db_connect`,
 };