Mention binary package distributions in public key page

Change-Id: I0692903498877e01f69694a3a62097e2f309d00e

releases/public-keys.md

diff --git a/releases/public-keys.md b/releases/public-keys.md
index 2c1b0a7..62fc983 100644
--- a/releases/public-keys.md
+++ b/releases/public-keys.md
@@ -5,6 +5,7 @@
 
 * Release artifacts that are deployed to Maven Central
 * Release announcement emails
+* Binary package distributions
 
 | Name             | Email Address                   | Fingerprint                                        | Notes     |
 |------------------|---------------------------------|----------------------------------------------------|-----------|