Avoid mentioning no library coverage

Author: jacknojo

docs/codeql/reusables/threat-model-description.rst

@@ -11,7 +11,7 @@ Note that subcategories can be turned included or excluded separately, so you ca
 
 The less commonly used categories are:
 
-- ``ai`` which represents output generated by large language models (LLMs). This threat model is opt-in and does not include any built-in source models.
+- ``ai`` which represents output generated by large language models (LLMs). This threat model is opt-in.
 - ``android`` which represents reads from external files in Android (``android-external-storage-dir``) and parameter of an entry-point method declared in a ``ContentProvider`` class (``contentprovider``). Currently only used by Java/Kotlin.
 - ``database-access-result`` which represents a database access. Currently only used by JavaScript.
 - ``file-write`` which represents opening a file in write mode. Currently only used in C#.