pypi/pypi/-/anaconda-project has an undefined version

This problem came up when trying to POST to https://api.clearlydefined.io/definitions?expand=-files with the following body, and get a 500 error as a result.
```
[
"pypi/pypi/-/anaconda-project/0.8.2"
]
```

If you search for `anaconda-project` on [the Clearly Defined website](https://clearlydefined.io/?sort=releaseDate&sortDesc=true&name=anaconda-project), there appears to be an `undefined` version. Turns out the component `anaconda-project` doesn't even exist on the [PyPi website](https://pypi.org/project/anaconda-project/) anymore.

We should standardize how to handle packages that no longer exist.
- Should we manually discover and remove the component(s) from Clearly Defined?
- Should there be some script that periodically checks for removed packages and handles them?