build(deps-dev): bump lodash from 4.17.19 to 4.17.21

Bumps [lodash](https://github.com/lodash/lodash) from 4.17.19 to 4.17.21.
- [Release notes](https://github.com/lodash/lodash/releases)
- [Commits](lodash/lodash@4.17.19...4.17.21)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package-lock.json

@@ -38,7 +38,7 @@
     "grunt-sass": "^3.1.0",
     "grunt-shell": "^1.1.2",
     "grunt-text-replace": "^0.4.0",
-    "lodash": "^4.17.19",
+    "lodash": "^4.17.21",
     "node-sass": "^4.5.3"
   },
   "scripts": {