`package.xml` depends on `python-numpy` on Noetic but should depend on `python3-noetic` ([L.18](https://github.com/eric-wieser/ros_numpy/blob/6758aa92210616c082d3fa63aedbc819d85e7744/package.xml#L18)). It seems to have been already [tested](https://github.com/eric-wieser/ros_numpy/issues/16#issuecomment-636989247).
