Bump axios from 0.20.0 to 0.21.1 in /backend

Bumps [axios](https://github.com/axios/axios) from 0.20.0 to 0.21.1.
- [Release notes](https://github.com/axios/axios/releases)
- [Changelog](https://github.com/axios/axios/blob/master/CHANGELOG.md)
- [Commits](axios/axios@v0.20.0...v0.21.1)

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

Author: dependabot[bot]

backend/package.json

@@ -10,7 +10,7 @@
   "author": "Christopher Klaus",
   "license": "ISC",
   "dependencies": {
-    "axios": "^0.20.0",
+    "axios": "^0.21.1",
     "body-parser": "^1.19.0",
     "cors": "^2.8.5",
     "express": "^4.17.1",

backend/yarn.lock

@@ -45,10 +45,10 @@ arraybuffer.slice@~0.0.7:
   resolved "https://registry.yarnpkg.com/arraybuffer.slice/-/arraybuffer.slice-0.0.7.tgz#3bbc4275dd584cc1b10809b89d4e8b63a69e7675"
   integrity sha512-wGUIVQXuehL5TCqQun8OW81jGzAWycqzFF8lFp+GOM5BXLYj3bKNsYC4daB7n6XjCqxQA/qgTJ+8ANR3acjrog==
 
-axios@^0.20.0:
-  version "0.20.0"
-  resolved "https://registry.yarnpkg.com/axios/-/axios-0.20.0.tgz#057ba30f04884694993a8cd07fa394cff11c50bd"
-  integrity sha512-ANA4rr2BDcmmAQLOKft2fufrtuvlqR+cXNNinUmvfeSNCOF98PZL+7M/v1zIdGo7OLjEA9J2gXJL+j4zGsl0bA==
+axios@^0.21.1:
+  version "0.21.1"
+  resolved "https://registry.yarnpkg.com/axios/-/axios-0.21.1.tgz#22563481962f4d6bde9a76d516ef0e5d3c09b2b8"
+  integrity sha512-dKQiRHxGD9PPRIUNIWvZhPTPpl1rf/OxTYKsqKUDjBwYylTvV7SjSHJb9ratfyzM6wCdLCOYLzs73qpg5c4iGA==
   dependencies:
     follow-redirects "^1.10.0"