Added a mention of /set_master_pass when it is not set

src/master_password_check.rs

@@ -31,9 +31,12 @@ async fn notify_about_no_master_pass(
     if let Some(error) = result {
         return Err(error.into());
     }
-    bot.send_message(msg.chat.id, "No master password set")
-        .reply_markup(deletion_markup())
-        .await?;
+    bot.send_message(
+        msg.chat.id,
+        "No master password set. Use /set_master_pass to set it",
+    )
+    .reply_markup(deletion_markup())
+    .await?;
     Ok(())
 }