gerrit: add more default plugins to improve user experience

Plugins added: singleusergroup, codemirror-editor, reviewnotes

Change-Id: I33c5e61b777143334a87ec3b65e81962b79d2dc9
diff --git a/core/installer/values-tmpl/gerrit.cue b/core/installer/values-tmpl/gerrit.cue
index 08a108d..0864cbd 100644
--- a/core/installer/values-tmpl/gerrit.cue
+++ b/core/installer/values-tmpl/gerrit.cue
@@ -288,6 +288,12 @@
 					}, {
 						name: "download-commands"
 					}, {
+						name: "singleusergroup"
+					}, {
+						name: "codemirror-editor"
+					}, {
+						name: "reviewnotes"
+					}, {
 						name: "oauth"
 						url: "https://drive.google.com/uc?export=download&id=1rSUpZCAVvHZTmRgUl4enrsAM73gndjeP"
 						sha1: "cbdc5228a18b051a6e048a8e783e556394cc5db1"