[docs] remove reference to signrawtransaction in the developer docs.

doc/developer-notes.md

@@ -952,8 +952,7 @@ A few guidelines for introducing and reviewing new RPC interfaces:
     from there.
 
 - A RPC method must either be a wallet method or a non-wallet method. Do not
-  introduce new methods such as `signrawtransaction` that differ in behavior
-  based on presence of a wallet.
+  introduce new methods that differ in behavior based on presence of a wallet.
 
   - *Rationale*: as well as complicating the implementation and interfering
     with the introduction of multi-wallet, wallet and non-wallet code should be