Need to specify @glimmer/reference as well for older versions of ember-source

Author: NullVoxPopuli

addon/tests/dummy/config/ember-try.js

@@ -41,6 +41,7 @@ module.exports = async function () {
         npm: {
           devDependencies: {
             '@glimmer/interfaces': '~0.84.3',
+            '@glimmer/reference': '~0.84.3',
             'ember-source': '~4.4.0',
             ...atTypes,
           },
@@ -51,6 +52,7 @@ module.exports = async function () {
         npm: {
           devDependencies: {
             '@glimmer/interfaces': '~0.84.3',
+            '@glimmer/reference': '~0.84.3',
             'ember-source': '~4.8.0',
           },
         },
@@ -60,6 +62,7 @@ module.exports = async function () {
         npm: {
           devDependencies: {
             '@glimmer/interfaces': '~0.84.3',
+            '@glimmer/reference': '~0.84.3',
             'ember-source': '~4.12.0',
           },
         },
@@ -69,6 +72,7 @@ module.exports = async function () {
         npm: {
           devDependencies: {
             '@glimmer/interfaces': '~0.84.3',
+            '@glimmer/reference': '~0.84.3',
             'ember-source': '~5.4.0',
           },
         },