postgresql::server::extension needs to have defaults for postgresql_psql

Using same pattern as with postgresql::server::database.
observed when installing the pg_trgm using pgsql 9.4

manifests/server/extension.pp

@@ -5,6 +5,19 @@ define postgresql::server::extension (
   $package_name = undef,
   $package_ensure = undef,
 ) {
+    $user          = $postgresql::server::user
+    $group         = $postgresql::server::group
+    $psql_path     = $postgresql::server::psql_path
+    $port          = $postgresql::server::port
+  
+    # Set the defaults for the postgresql_psql resource
+    Postgresql_psql {
+      psql_user  => $user,
+      psql_group => $group,
+      psql_path  => $psql_path,
+      port       => $port,
+    }
+
   case $ensure {
     'present': {
       $command = "CREATE EXTENSION ${name}"