pyhf v0.7.2 released

[pyhf announcements]

Dear pyhf users,

We're happy to announce that pyhf v0.7.2 is out now on PyPI and Conda-forge! This is a patch release with a small fix contributed by Alexander Held and a bug fix regarding typing. There are no API changes and no changes in dependency lower bounds, so we encourage you to update to v0.7.2

```
python -m pip install --upgrade pyhf
```

Below we list the most important points from the release notes:

* If a multiple component parameter of interest is used raise pyhf.exceptions.InvalidModel. This guards against modifiers like shapefactor, shapesys, and staterror from being used as POIs.
* Use typing.TYPE_CHECKING guard to avoid causing a ModuleNotFoundError when the version of NumPy installed is older than v1.21.0, which is the first NumPy release to include numpy.typing.

Thank you for using pyhf and for continuing to provide us feedback on both new feature requests as well as sharing your bug reports and user experiences through the recommended channels.

Best,
The pyhf dev team (Matthew, Lukas, and Giordon)