Bump tightenco/collect from 5.8.34 to 6.0.0 in /drupal

Bumps [tightenco/collect](https://github.com/tightenco/collect) from 5.8.34 to 6.0.0.
- [Release notes](https://github.com/tightenco/collect/releases)
- [Commits](https://github.com/tightenco/collect/compare/v5.8.34...v6.0.0)

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

drupal/composer.json

@@ -25,7 +25,7 @@
         "drupal/core": "^8.7.0",
         "drush/drush": "^9.0.0",
         "josephlavin/tap": "^1.0",
-        "tightenco/collect": "^5.8",
+        "tightenco/collect": "^6.0",
         "vlucas/phpdotenv": "^2.4",
         "webflo/drupal-finder": "^1.0.0",
         "webmozart/path-util": "^2.3",