Bump axios from 0.19.2 to 0.21.2

Bumps [axios](https://github.com/axios/axios) from 0.19.2 to 0.21.2.
- [Release notes](https://github.com/axios/axios/releases)
- [Changelog](https://github.com/axios/axios/blob/v0.21.2/CHANGELOG.md)
- [Commits](axios/axios@v0.19.2...v0.21.2)

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

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

Author: dependabot[bot]

package-lock.json

@@ -227,7 +227,7 @@
 	"dependencies": {
 		"@hackmd/api": "^1.1.1",
 		"ajax": "0.0.4",
-		"axios": "^0.19.2",
+		"axios": "^0.21.2",
 		"bootstrap3": "^3.3.5",
 		"fs": "0.0.1-security",
 		"markdown-it-abbr": "^1.0.4",