Add missing base.tgz artifact to release configuration

Change-Id: I9f01dcf01d184ba70fffbac8e33003e227d12074
diff --git a/kokoro/release.cfg b/kokoro/release.cfg
index 47c21c2..86fc779 100644
--- a/kokoro/release.cfg
+++ b/kokoro/release.cfg
@@ -6,6 +6,7 @@
 gfile_resources: "/x20/teams/spacepark/enterprise/kokoro/prod/spacepark/enterprise/debs/apex.deb"
 gfile_resources: "/x20/teams/spacepark/enterprise/kokoro/prod/spacepark/enterprise/docker/arm64-builder.tar"
 gfile_resources: "/x20/teams/spacepark/enterprise/kokoro/prod/spacepark/enterprise/docker/aiy-board-builder.tar"
+gfile_resources: "/x20/teams/spacepark/enterprise/kokoro/prod/spacepark/enterprise/pbuilder/base.tgz"
 
 action {
   define_artifacts {