Fix host site for docs

[kemccusker]

Per PR #254, we need to update how the docs are hosted. The link in the PR no longer works.

[brews]

From the linked PR, it seems like it was just mkdocs hosted on Github Pages.
From the link on the DSCIM's repo page it looks like docs are up on https://climateimpactlab.github.io/dscim/.

Is there something wrong with these docs or a specific feature missing, @kemccusker?

[kemccusker]

OH, thanks, @brews. I was looking at the link mentioned in the PR, which points to Jonah's personal account, and which is now defunct. Thanks, I didn't notice the real link listed in DSCIM. I will close this.