Bump laravel-mix from 6.0.37 to 6.0.39

Bumps [laravel-mix](https://github.com/JeffreyWay/laravel-mix) from 6.0.37 to 6.0.39.
- [Release notes](https://github.com/JeffreyWay/laravel-mix/releases)
- [Changelog](https://github.com/laravel-mix/laravel-mix/blob/master/CHANGELOG.md)
- [Commits](laravel-mix/laravel-mix@v6.0.37...v6.0.39)

---
updated-dependencies:
- dependency-name: laravel-mix
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package-lock.json

@@ -12,7 +12,7 @@
     "devDependencies": {
         "cross-env": "^7.0.3",
         "css-loader": "^5.2.6",
-        "laravel-mix": "^6.0.37",
+        "laravel-mix": "^6.0.39",
         "lodash": "^4.17.21",
         "pace": "0.0.4",
         "resolve-url-loader": "^4.0.0",