message: remove panic from UnsharedMemory
diff: @@ -231,7 +231,11 @@ impl UnsharedMemory {
  MemoryType::Static => {
  UnsharedMemoryStorage::Static(StaticMemory::new(desc, &mut local)?)
  }
  - MemoryType::SharedStatic => panic!("attempting to create shared unshared memory"),
  + MemoryType::SharedStatic => {
  + return Err(CreationError::InvalidDescriptor(
  + "attempting to create shared unshared memory".to_string(),
  + ));
  + }
  };
  Ok(Self {
  