Show neighbor cells if boats can't touch

rust/sea_battle_backend/src/data/boats_layout.rs

@@ -318,7 +318,7 @@ impl BoatsLayout {
                         .iter()
                         .any(|c| boat_j_coords.contains(c))
                 {
-                    errors.push("A collision between two boats has been detected!");
+                    errors.push("Two boats are touching!");
                 }
             }
         }