lib: fix incorrect encoding of Signature (incompatible with decoding, but never used together) - breaks backward compatibility for remote control connections (#1765)

* lib: fix incorrect StrEncoding of Signature (it was not compatible with decoding, but was never used)

* align encoding with used in links (breaks backward compatibility)

src/Simplex/RemoteControl/Invitation.hs

@@ -108,9 +108,9 @@ instance StrEncoding RCSignedInvitation where
     mconcat
       [ strEncode invitation,
         "&ssig=",
-        strEncode $ C.signatureBytes ssig,
+        strEncode ssig,
         "&idsig=",
-        strEncode $ C.signatureBytes idsig
+        strEncode idsig
       ]
 
   strP = do