Update dependency ember-bootstrap to v4.6.3

Author: renovate-bot

Diff for: ember/package.json

@@ -42,7 +42,7 @@
     "broccoli-asset-rev": "3.0.0",
     "ember-ajax": "5.0.0",
     "ember-auto-import": "1.10.1",
-    "ember-bootstrap": "4.3.0",
+    "ember-bootstrap": "4.6.3",
     "ember-cli": "3.25.0",
     "ember-cli-babel": "7.23.1",
     "ember-cli-bundle-analyzer": "0.2.2",