Fix jar setting from full build

src-tauri/src/unzip.rs

@@ -99,7 +99,7 @@ pub fn unzip(
     // If downloading full build, emit that the jar was extracted with it
     if zipfile == "GrasscutterCulti3.4.zip" {
       window
-        .emit("jar_extracted", destpath.to_string() + &((destpath.to_string() + "grasscutter.jar")))
+        .emit("jar_extracted", destpath.to_string() + "grasscutter.jar")
         .unwrap();
     }