docs(skills): regenerate alert card for --integration

Regenerate the GENERATED:alert fence in skills/flashduty/reference/alert.md via make gen-cards to pick up the new --integration flag on alert list.

Author: ysyneu

skills/flashduty/reference/alert.md

@@ -90,6 +90,7 @@ List alerts
 - `--active` bool
 - `--channel` string
 - `--fields` string
+- `--integration` string
 - `--limit` int
 - `--muted` bool
 - `--page` int