fix special char

Author: sebastian-iancu

docs/UML/classes/org.openehr.am.aom2.c_string.adoc

@@ -20,7 +20,7 @@ h|*0..1 +
 |*constraint*: `link:/releases/BASE/{base_release}/foundation_types.html#_list_class[List^]<link:/releases/BASE/{base_release}/foundation_types.html#_string_class[String^]>`
 a|String constraint - a list of literal strings and / or regular expression strings delimited by the ‘/’ character.
 
-To represent no constraint, use an empty list, or alternatively, a regex 'any' pattern, i.e. `/.*/`.
+To represent no constraint, use an empty list, or alternatively, a regex 'any' pattern, i.e. `/.&#42;/`.
 
 h|*0..1 +
 (effected)*