in_mem: add examples for yaml configuration

Signed-off-by: Takahiro Yamashita <[email protected]>

pipeline/inputs/memory-metrics.md

@@ -27,6 +27,8 @@ Fluent Bit v1.x.x
 
 In your main configuration file append the following _Input_ & _Output_ sections:
 
+{% tabs %}
+{% tab title="fluent-bit.conf" %}
 ```python
 [INPUT]
     Name   mem
@@ -36,4 +38,17 @@ In your main configuration file append the following _Input_ & _Output_ sections
     Name   stdout
     Match  *
 ```
-
+{% endtab %}
+
+{% tab title="fluent-bit.yaml" %}
+```yaml
+pipeline:
+    inputs:
+        - name: mem
+          tag: memory
+    outputs:
+        - name: stdout
+          match: '*'
+```
+{% endtab %}
+{% endtabs %}