[Security] Bump bootstrap from 4.1.3 to 4.3.1

Bumps [bootstrap](https://github.com/twbs/bootstrap) from 4.1.3 to 4.3.1. **This update includes security fixes.**
- [Release notes](https://github.com/twbs/bootstrap/releases)
- [Commits](twbs/bootstrap@v4.1.3...v4.3.1)

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

package.json

@@ -17,7 +17,7 @@
     "@fortawesome/fontawesome-svg-core": "^1.2.7",
     "@fortawesome/free-solid-svg-icons": "^5.4.2",
     "@fortawesome/react-fontawesome": "^0.1.3",
-    "bootstrap": "^4.1.3",
+    "bootstrap": "^4.3.1",
     "cross-fetch": "^2.2.3",
     "date-fns": "^1.29.0",
     "flow-bin": "^0.85.0",