Document No hosts matched the subscripted pattern (#2481)

Fixes: #2422
ansible · Sep 21, 2022 · e00891b · e00891b
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commit e00891b
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diff --git a/src/ansiblelint/_internal/internal_error.md b/src/ansiblelint/_internal/internal_error.md
@@ -31,3 +31,13 @@ them to the `exclude_paths`.
   hosts: localhost
   tasks: []
 ```
+
+## ERROR! No hosts matched the subscripted pattern
+
+If you see this error, it means that you tried to index a host group variable
+that is using an index above its size.
+
+Instead of doing something like `hosts: all[1]` which assumes that you have
+at least two hosts in your current inventory, you better write something like
+`hosts: "{{ all[1] | default([]) }}`, which is safe and do not produce runtime
+errors. Use safe fallbacks to make your code more resilient.