exa: add --header, --git and --git-ignore examples (#5749)

pages/common/exa.md

@@ -26,3 +26,11 @@
 - List files sorted by modification date (oldest first):
 
 `exa --long --sort={{modified}}`
+
+- List files with their headers, icons, and Git statuses:
+
+`exa --long --header --icons --git`
+
+- Don't list files mentioned in `.gitignore`:
+
+`exa --git-ignore`