fix msg type equality bug

src/messages.rs

@@ -32,7 +32,7 @@ pub struct SsbMessageValue {
 }
 
 /// Message content types.
-#[derive(Debug)]
+#[derive(Debug, PartialEq)]
 #[allow(missing_docs)]
 pub enum SsbMessageContentType {
     About,
@@ -70,12 +70,10 @@ impl SsbMessageValue {
 
     /// Helper function which returns `true` if this message is of the given type,
     /// and `false` if the type does not match or is not found.
-    pub fn is_message_type(&self, _message_type: SsbMessageContentType) -> bool {
+    pub fn is_message_type(&self, message_type: SsbMessageContentType) -> bool {
         let self_message_type = self.get_message_type();
         match self_message_type {
-            Ok(mtype) => {
-                matches!(mtype, _message_type)
-            }
+            Ok(mtype) => mtype == message_type,
             Err(_err) => false,
         }
     }