Remove more unwrap

src/fs.rs

@@ -4,10 +4,10 @@ use crate::notification::NotificationData;
 use crate::notification::NotificationData::PermissionDenied;
 
 pub fn app_data_dir() -> PathBuf {
-    let mut dir = dirs::data_dir().unwrap();
+    let mut dir = dirs::data_dir().expect("Unsupported OS");
     dir.push("jap_learn");
     if !dir.exists() {
-        fs::create_dir_all(dir.clone()).unwrap();
+        fs::create_dir_all(dir.clone()).expect("Unable to create directory");
     }
 
     dir