Fix for #679 (^^ and the end of the string)

Author: AlexDaniel

doc/Language/regexes.pod6

@@ -484,7 +484,8 @@ Keep in mind, these anchors match end of B<string>, not line:
 =head2 X«C<^^>, Start of Line and C<$$>, End of Line|regex,^^;regex,$$»
 
 The C<^^> assertion matches at the start of a logical line. That is, either
-at the start of the string, or after a newline character.
+at the start of the string, or after a newline character. It does not match
+at the end of the string, even if it ends with a newline character.
 
 C<$$> matches only at the end of a logical line, that is, before a newline
 character, or at the end of the string when the last character is not a