Implement Default for raw::Client and wrapper::ListenBrainz

Following clippy recommendations

src/raw/client.rs

@@ -348,3 +348,9 @@ impl Client {
         ResponseType::from_response(response)
     }
 }
+
+impl Default for Client {
+    fn default() -> Self {
+        Self::new()
+    }
+}

src/wrapper.rs

@@ -147,3 +147,9 @@ impl ListenBrainz {
         self.submit_listen(ListenType::PlayingNow, None, artist, track, release)
     }
 }
+
+impl Default for ListenBrainz {
+    fn default() -> Self {
+        Self::new()
+    }
+}