inv: Emoji consistency

The slot switching action had a different emoji for confirming the
command was successful compared to other actions, so I switched it for
the green checkmark.

src/inv.rs

@@ -187,7 +187,7 @@ pub fn switch(message: bool) -> Result<()> {
     })?;
 
     if message {
-        println!("🎉 {}", "Switched inventory slots!".green());
+        println!("✅ {}", "Switched inventory slots!".green());
     }
     Ok(())
 }