docs: link to checklist in voting document that is linked in every em…

…ail (#287)



Co-authored-by: Norman Breau <norman@normanbreau.com>

docs/release-voting.md

@@ -21,6 +21,8 @@
 
 # Release Voting Guidelines
 
+> This document describes what Apache requires you to do for a vote. Please make sure you understand this first. You can refer to the [shorter checklist](./vote-checklist.md) every time you vote.
+
 Reference: https://www.apache.org/dev/release-publishing.html
 
 Apache releases require at least 3 +1 votes, and there must be more +1s than -1s.