Retemplate all SunPy Maintained Packages

[Cadair]

### Initial Retemplate of all repos
- [ ] radiospectra : https://github.com/sunpy/radiospectra/pull/115
- [x] sunkit-spex : https://github.com/sunpy/sunkit-spex/pull/159
- [x] sunraster : https://github.com/sunpy/sunraster/pull/259
- [x] drms : https://github.com/sunpy/drms/pull/120
- [x] sunkit-instruments : https://github.com/sunpy/sunkit-instruments/pull/133
- [x] sunkit-pyvista : https://github.com/sunpy/sunkit-pyvista/pull/163
- [x] sunkit-image : https://github.com/sunpy/sunkit-image/pull/202
- [x] mpl-animators : https://github.com/sunpy/mpl-animators/pull/48
- [x] sunkit-dem : https://github.com/sunpy/sunkit-dem/pull/33
- [x] sunpy : https://github.com/sunpy/sunpy/pull/7494
- [x] streamtracer : https://github.com/sunpy/streamtracer/pull/111
- [x] sunkit-magex
- [x] soar : https://github.com/sunpy/sunpy-soar/pull/116
- [x] ndcube : https://github.com/sunpy/ndcube/pull/672

[nabobalis]

I am trying my hand at this with sunkit-dem here: https://github.com/sunpy/sunkit-dem/pull/33

[Cadair]

Thanks @nabobalis