Upgrade ember power select

This also gets rid of node-sass and upgrades node, and deletes an unused osf-logo component which was doing something deprecated in our current version of sass.

ember-cli-build.js

@@ -1,6 +1,5 @@
 /* eslint-env node */
 
-const nodeSass = require('node-sass');
 
 const EmberApp = require('ember-cli/lib/broccoli/ember-app');
 const broccoliAssetRevDefaults = require('broccoli-asset-rev/lib/default-options');
@@ -49,7 +48,6 @@ module.exports = function(defaults) {
             prepend: config.assetsPrefix,
         },
         sassOptions: {
-            implementation: nodeSass,
             includePaths: [
                 'app/styles/',
             ],

package.json

@@ -194,7 +194,7 @@
     "ember-page-title": "^6.2.2",
     "ember-parachute": "^1.0.2",
     "ember-percy": "^1.5.0",
-    "ember-power-select": "^4.1.7",
+    "ember-power-select": "6.0.1",
     "ember-qrcode-shim": "^0.4.0",
     "ember-qunit": "^5.1.5",
     "ember-radio-button": "3.0.0-beta.1",
@@ -236,7 +236,6 @@
     "mime-types": "^2.1.22",
     "mocha": "^6.1.4",
     "moment-timezone": "^0.5.43",
-    "node-sass": "^4.14.0",
     "npm-run-all": "^4.1.5",
     "prettier": "^2.5.1",
     "qunit": "^2.17.2",
@@ -257,7 +256,7 @@
     "node": "12.* || 14.* || >= 16"
   },
   "volta": {
-    "node": "14.15.0",
+    "node": "16.20.2",
     "yarn": "1.21.1"
   },
   "ember": {