Set Gerrit to 3.2.0-rc4

Change-Id: If4fbc5b39f9ec3784e822ae258ba2f7c7eb9e2df
diff --git a/common.env b/common.env
index be6480b..e7f2eeb 100644
--- a/common.env
+++ b/common.env
@@ -5,7 +5,7 @@
 
 # Gerrit version
 GERRIT_VERSION=3.2
-GERRIT_PATCH=0-rc3
+GERRIT_PATCH=0-rc4
 GERRIT_BRANCH=stable-$(GERRIT_VERSION)
 
 # Gerrit CI