Bump axios from 0.19.0 to 0.21.2 in /frontend (#304)

Bumps [axios](https://github.com/axios/axios) from 0.19.0 to 0.21.2.
- [Release notes](https://github.com/axios/axios/releases)
- [Changelog](https://github.com/axios/axios/blob/master/CHANGELOG.md)
- [Commits](axios/axios@v0.19.0...v0.21.2)

---
updated-dependencies:
- dependency-name: axios
  dependency-type: direct:production
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

frontend/package-lock.json

@@ -37,7 +37,7 @@
     "core-js": "^2.6.5",
     "acorn": "^6.0.5",
     "animate.css": "3.7.2",
-    "axios": "^0.19.0",
+    "axios": "^0.21.2",
     "bulma": "^0.7.5",
     "font-awesome": "^4.7.0",
     "jdenticon": "^2.1.1",