Bump electron from 4.2.12 to 7.2.4

Bumps [electron](https://github.com/electron/electron) from 4.2.12 to 7.2.4.
- [Release notes](https://github.com/electron/electron/releases)
- [Changelog](https://github.com/electron/electron/blob/master/docs/breaking-changes.md)
- [Commits](electron/electron@v4.2.12...v7.2.4)

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

Author: dependabot[bot]

package.json

@@ -148,7 +148,7 @@
     "css-loader": "^0.19.0",
     "devtron": "^1.1.0",
     "dom-storage": "^2.0.2",
-    "electron": "4",
+    "electron": "7",
     "electron-debug": "^2.2.0",
     "electron-devtools-installer": "^2.2.4",
     "electron-packager": "^12.2.0",