fix: ui/packages/consul-ui/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-INFLIGHT-6095116
- https://snyk.io/vuln/SNYK-JS-JSON5-3182856

ui/packages/consul-ui/package.json

@@ -96,7 +96,7 @@
     "ember-cli-babel": "^7.17.2",
     "ember-cli-code-coverage": "^1.0.0-beta.4",
     "ember-cli-dependency-checker": "^3.2.0",
-    "ember-cli-flash": "^2.1.1",
+    "ember-cli-flash": "^5.0.0",
     "ember-cli-htmlbars": "^5.2.0",
     "ember-cli-inject-live-reload": "^2.0.2",
     "ember-cli-page-object": "^1.16.2",