Changing default file format for the snippets from TOML to YAML

docs/content/observability/metrics/overview.md

@@ -11,14 +11,14 @@ Traefik supports 4 metrics backends:
 
 To enable metrics:
 
-```toml tab="File (TOML)"
-[metrics]
-```
-
 ```yaml tab="File (YAML)"
 metrics: {}
 ```
 
+```toml tab="File (TOML)"
+[metrics]
+```
+
 ```bash tab="CLI"
 --metrics=true
 ```