Bump bootstrap from 4.2.1 to 4.3.1

Bumps [bootstrap](https://github.com/twbs/bootstrap) from 4.2.1 to 4.3.1.
- [Release notes](https://github.com/twbs/bootstrap/releases)
- [Commits](twbs/bootstrap@v4.2.1...v4.3.1)

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

Author: dependabot[bot]

package-lock.json

@@ -22,7 +22,7 @@
 		"autoprefixer": "9.6.1",
 		"babel-loader": "8.0.6",
 		"babel-plugin-import-glob": "2.0.0",
-		"bootstrap": "4.2.1",
+		"bootstrap": "4.3.1",
 		"classnames": "2.2.6",
 		"copy-webpack-plugin": "5.0.4",
 		"cross-env": "5.2.0",