Remove package.documentation from the “before publishing” list.

crates.io currently automatically links to `docs.rs` if `documentation` is not specified, which is usually a good choice.

Author: kpreid

src/doc/src/reference/publishing.md

@@ -50,7 +50,6 @@ you have filled out the following fields:
 - [`license` or `license-file`]
 - [`description`]
 - [`homepage`]
-- [`documentation`]
 - [`repository`]
 - [`readme`]