Recognise macaroons as access tokens from Synapse

Author: reivilibre

crates/data-model/src/tokens.rs

@@ -294,7 +294,8 @@ impl TokenType {
     pub fn check(token: &str) -> Result<TokenType, TokenFormatError> {
         // these are legacy tokens imported from Synapse
         // we don't do any validation on them and continue as is
-        if token.starts_with("syt_") {
+        // Tokens starting `MDAx` are macaroons from even older versions of Synapse.
+        if token.starts_with("syt_") || token.starts_with("MDAx") {
             return Ok(TokenType::CompatAccessToken);
         }
         if token.starts_with("syr_") {