do not print anything if no user id was found

meilisearch-http/src/analytics.rs

@@ -182,7 +182,7 @@ impl MockAnalytics {
     pub fn new(opt: &Opt) -> &'static Self {
         let user = read_to_string(opt.db_path.join("user-id"))
             .or_else(|_| read_to_string("/tmp/meilisearch-user-id"))
-            .unwrap_or_else(|_| "No user-id".to_string());
+            .unwrap_or_else(|_| "".to_string());
         let analytics = Box::new(Self { user });
         Box::leak(analytics)
     }

meilisearch-http/src/main.rs

@@ -126,7 +126,11 @@ Anonymous telemetry:   \"Enabled\""
             );
         }
     }
-    eprintln!("Unique User ID:\t\"{}\"", analytics);
+
+    let analytics = analytics.to_string();
+    if analytics != "" {
+        eprintln!("Unique User ID:\t\"{}\"", analytics);
+    }
 
     eprintln!();