fix ref

draft-schinazi-masque-proxy.md

@@ -112,7 +112,7 @@ The fact that MASQUE is layered over HTTP makes it much more resilient to
 detection. To network observers, the unencrypted bits in a QUIC connection
 used for MASQUE are indistinguishable from those of a regular Web browsing
 connection. Separately, if paired with a non-probeable HTTP authentication
-scheme {{?SIGNATURE-AUTH=I-D.ietf-httpbis-unprompted-auth}}, any Web server
+scheme {{?CONCEALED-AUTH=I-D.ietf-httpbis-unprompted-auth}}, any Web server
 can also become a MASQUE proxy while remaining indistinguishable from a
 regular Web server. It might still be possible to detect some level of
 MASQUE usage by analyzing encrypted traffic patterns, however the cost of