Yarn upgrade

package.json

@@ -37,7 +37,7 @@
     "ember-decorators": "^6.1.1",
     "ember-headroom": "^1.1.2",
     "ember-router-service-polyfill": "^1.0.2",
-    "sass": "^1.24.0"
+    "sass": "^1.26.10"
   },
   "devDependencies": {
     "@ember/optional-features": "^1.3.0",
@@ -55,7 +55,7 @@
     "ember-cli-deploy-build": "^2.0.0",
     "ember-cli-deploy-ghpages": "^0.2.0",
     "ember-cli-inject-live-reload": "^2.0.2",
-    "ember-cli-stylelint": "^3.0.2",
+    "ember-cli-stylelint": "^4.0.0",
     "ember-cli-uglify": "^3.0.0",
     "ember-disable-prototype-extensions": "^1.1.3",
     "ember-export-application-global": "^2.0.1",
@@ -65,7 +65,7 @@
     "ember-qunit": "^4.6.0",
     "ember-resolver": "^8.0.0",
     "ember-source": "~3.20.2",
-    "ember-source-channel-url": "^2.0.1",
+    "ember-source-channel-url": "^3.0.0",
     "ember-template-lint": "^2.9.1",
     "ember-try": "^1.4.0",
     "eslint": "^7.5.0",