Release notes for other versions not correctly linked

[Bob-The-Marauder]

When looking at https://www.tiot.jp/riak-docs/riak/kv/2.2.3/release-notes/ there are links to the 2.2.2 and 2.2.1 release notes at the bottom of the page. However, both links point to 2.2.3 release notes. This looks like a find and replace that was botched by accident. However, we should probably check all release notes to confirm.