Bump lodash from 4.17.15 to 4.17.21 in /app

Bumps [lodash](https://github.com/lodash/lodash) from 4.17.15 to 4.17.21.
- [Release notes](https://github.com/lodash/lodash/releases)
- [Commits](https://github.com/lodash/lodash/compare/4.17.15...4.17.21)

Signed-off-by: dependabot[bot] <support@github.com>

app/package-lock.json

@@ -2362,9 +2362,9 @@
       }
     },
     "lodash": {
-      "version": "4.17.15",
-      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.15.tgz",
-      "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A=="
+      "version": "4.17.21",
+      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.21.tgz",
+      "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg=="
     },
     "lodash-es": {
       "version": "4.17.15",

app/package.json

@@ -41,7 +41,7 @@
     "font-awesome": "^4.7.0",
     "immutable": "^3.8.2",
     "jquery": "^3.4.1",
-    "lodash": "^4.17.15",
+    "lodash": "^4.17.21",
     "lodash-es": "^4.17.15",
     "moment": "^2.24.0",
     "querystring": "^0.2.0",