Bump vlucas/phpdotenv from 5.3.1 to 5.4.0

Bumps [vlucas/phpdotenv](https://github.com/vlucas/phpdotenv) from 5.3.1 to 5.4.0.
- [Release notes](https://github.com/vlucas/phpdotenv/releases)
- [Commits](vlucas/phpdotenv@v5.3.1...v5.4.0)

---
updated-dependencies:
- dependency-name: vlucas/phpdotenv
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

composer.json

@@ -33,7 +33,7 @@
   "require": {
     "php": ">=7.1",
     "composer/installers": "^1.12",
-    "vlucas/phpdotenv": "^5.3",
+    "vlucas/phpdotenv": "^5.4",
     "oscarotero/env": "^2.1",
     "roots/bedrock-autoloader": "^1.0",
     "roots/bedrock-disallow-indexing": "^2.0",