Ban reserved annotations in "note", "adaptation_meta" directives (#561)
Squid defines a list of names used internally for exchanging name=value
pairs with various helpers. When Squid receives a name=value pair with a
reserved name, Squid stores it as if it was any other annotation; the
information can be checked with a "note" ACL and logged with %note. An
admin who configures a custom annotation with the same reserved name may
see strange/unexpected results such as seemingly corrupted access.log
record fields and mismatching ACLs.
Squid already prohibits reserved annotation names in
annotate_transaction and annotate_client ACLs. This change adds the
missing protection to the "note" and adaptation_meta directives.