Merge pull request GoogleCloudPlatform#525 from donmccasland/update-versions

Updating PHP versions 7.3.23 and 7.2.34

Author: donmccasland

scripts/ubuntu-packages.cfg

@@ -5,6 +5,6 @@ env_vars {
 
 env_vars {
   key: "PHP_VERSIONS"
-  value: "7.3.19-1,7.2.33-1,7.1.33-1"
+  value: "7.3.23-1,7.2.34-1,7.1.33-1"
 }