chore(deps): Bump vlucas/phpdotenv from 4.1.5 to 4.1.8

Bumps [vlucas/phpdotenv](https://github.com/vlucas/phpdotenv) from 4.1.5 to 4.1.8.
- [Release notes](https://github.com/vlucas/phpdotenv/releases)
- [Commits](vlucas/phpdotenv@v4.1.5...v4.1.8)

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

composer.json

@@ -33,7 +33,7 @@
   "require": {
     "php": ">=7.1",
     "composer/installers": "^1.8",
-    "vlucas/phpdotenv": "^4.1.5",
+    "vlucas/phpdotenv": "^4.1.8",
     "oscarotero/env": "^2.0",
     "roots/bedrock-autoloader": "^1.0",
     "roots/wordpress": "5.4.1",