Update create_metric_extension.md

formatting changes

Author: rishabh-ghosh24

manageability-and-operations/observability-and-manageability/database-management/Custom Metrics/create_metric_extension.md

@@ -222,7 +222,7 @@ PDB-level metrics will appear under the same monitoring namespace but will be sp
   - Required privileges are missing.
   - Output columns or types are incorrect.
 
-Here's an example of what an incorrect SQL query error would look like during Test phase.
+Here's an example of what an incorrect SQL query error would look like during Test phase.<br>
 <img src="./images/ME20.png" height="100" width="200"><br>
 Hence login to the DB beforehand and test the SQL first to ensure the queries are valid and return the expected data.