Update to the real version 4.4.1; r408807 was actually a beta.

Here's what happened (see also GitHub issue #6250 for elastic/kibana):

• The tag for 4.4.1 appeared on GitHub

• The port was updated to 4.4.1 using the release tarball from elastic.co, with a matching name

• The tarball was actually a beta from a commit that was not pushed

• The port broke once the tarball from the actual release came up for download, with exactly the same name

The commit id from package.json now matches the commit from the upstream
repo. This should be used in the future to check if tarballs actually match
releases.

Approved by: maintainer (by mail)