Merge pull request #6748 from EnterpriseDB/efm/release-date-support

Add information about support expiration to release notes.

Author: djw-m

product_docs/docs/efm/5/efm_rel_notes/index.mdx

@@ -1,8 +1,7 @@
 ---
 title: "Release notes"
 ---
-The Failover Manager documentation describes the latest version of Failover Manager. These release notes
-cover what was new in each release.
+The Failover Manager documentation describes the latest version of Failover Manager. These release notes cover what was new in each release. The standard support end date for each release is 18 months after the next release.
 
 | Version | Release Date |
 | ------- | ------------ |