Make lint fail on warnings

.github/workflows/code-quality.yml

@@ -23,7 +23,7 @@ jobs:
         run: cargo fmt --check 
 
       - name: Lint
-        run: cargo clippy
+        run: cargo clippy -- -D warnings
 
       - name: Tests
         run: cargo test

src/client.rs

@@ -17,7 +17,7 @@ impl<'a> Client {
         Client { discord_client }
     }
 
-    pub async fn connect_discord(&mut self) -> () {
+    pub async fn connect_discord(&mut self) {
         if let Err(error) = self.discord_client.start().await {
             println!("Could not connect to Discord: {:?}", error);
         }