Update password.py documentation (#80297)

* Update password.py documentation with new semantic markup

lib/ansible/plugins/lookup/password.py

@@ -45,6 +45,9 @@ DOCUMENTATION = """
         version_added: "1.4"
         description:
           - A list of names that compose a custom character set in the generated passwords.
+          - This parameter defines the possible character sets in the resulting password, not the required character sets.
+            If you want to require certain character sets for passwords, you can use the C(community.general.random_string lookup) plugin -
+            P(community.general.random_string#lookup).
           - 'By default generated passwords contain a random mix of upper and lowercase ASCII letters, the numbers 0-9, and punctuation (". , : - _").'
           - "They can be either parts of Python's string module attributes or represented literally ( :, -)."
           - "Though string modules can vary by Python version, valid values for both major releases include: