message: [pdsl_core] Add storage::HashMap::get unit test
diff: @@ -68,6 +68,20 @@ fn remove() {
  assert_eq!(map.len(), 0);
  }
  +#[test]
  +fn get() {
  + let mut map = unsafe {
  + storage::HashMap::<String, String>::new_unchecked(Key([0x77; 32]))
  + };
  + // Inserts some elements
  + assert_eq!(map.insert("Black".into(), "White".into()), None);
  + assert_eq!(map.insert("Up".into(), "Down".into()), None);
  + // Check if get returns the right answer
  + assert_eq!(map.get("Black"), Some(&"White".into()));
  + assert_eq!(map.get("Up"), Some(&"Down".into()));
  + assert_eq!(map.get("Forward"), None);
  +}
  +
  #[test]
  fn mutate_with() {
  let mut map = unsafe {
  