FIX broken link to docs
This appears to be the updated link based on search.
@@ -50,7 +50,7 @@ build:
skip: true # [win]
```
-A full description of selectors is [in the conda docs](http://conda.pydata.org/docs/building/meta-yaml.html#preprocessing-selectors).
+A full description of selectors is [in the conda docs](https://docs.conda.io/projects/conda-build/en/latest/resources/define-metadata.html#preprocessing-selectors).
Additionally, when pushing commits for a recipe that excludes Windows, put `[skip appveyor]` in the commit message to prevent CI tests
on Windows from even starting.
