fix

Author: chcomley

docs/project/wiki/markdown-guidance.md

@@ -75,15 +75,14 @@ The following Markdown creates a top-level header (H1) and four levels of subhea
 ### This is a lower subheader (H3)
 #### This is an H4 header
 ##### This is an H5 header
+```
 
 The following image shows the published view of the Markdown:
 
 :::image type="content" source="media/markdown-guidance/markdown-headers.png" alt-text="Screenshot of the published view of Markdown syntax for five levels of headers.":::
 
-
 ## Paragraphs and line breaks
 
-
 > [!IMPORTANT]
 > Azure DevOps Markdown handles line breaks differently than most other Markdown implementations. To create a line break (soft return) within a paragraph, add two spaces at the end of the line before you press **Enter**. If you press **Enter** without the two spaces, the published output doesn't include a line break.