chore(deps): stable ember infrastructure

Author: renovate-bot

package.json

@@ -46,7 +46,7 @@
     "ember-cli-app-version": "3.2.0",
     "ember-cli-dependency-checker": "3.2.0",
     "ember-cli-eslint": "5.1.0",
-    "ember-cli-htmlbars": "5.7.1",
+    "ember-cli-htmlbars": "6.0.0",
     "ember-cli-htmlbars-inline-precompile": "3.0.2",
     "ember-cli-inject-live-reload": "2.1.0",
     "ember-cli-sri": "2.1.1",
@@ -59,7 +59,7 @@
     "ember-maybe-import-regenerator": "0.1.6",
     "ember-qunit": "5.1.5",
     "ember-resolver": "8.0.3",
-    "ember-source": "3.28.2",
+    "ember-source": "4.0.0",
     "ember-welcome-page": "4.0.0",
     "eslint-plugin-ember": "10.5.7",
     "husky": "1.3.1",