Bump eventsource from 1.0.7 to 1.1.2

Bumps [eventsource](https://github.com/EventSource/eventsource) from 1.0.7 to 1.1.2.
- [Changelog](https://github.com/EventSource/eventsource/blob/master/HISTORY.md)
- [Commits](https://github.com/EventSource/eventsource/compare/v1.0.7...v1.1.2)

---
updated-dependencies:
- dependency-name: eventsource
  dependency-type: indirect
...

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

package.json

@@ -16,7 +16,7 @@
         "cross-env": "^5.1",
         "imagemin": "^6.0.0",
         "jquery": ">=3.4.0",
-        "laravel-mix": "^6.0.49",
+        "laravel-mix": "^4.0.15",
         "lodash": "^4.17.5",
         "popper.js": "^1.14.7",
         "resolve-url-loader": "^2.3.2",