Update symfony/var-dumper requirement from ^6.2 to ^6.2 || ^7.0 (#563)

Updates the requirements on [symfony/var-dumper](https://github.com/symfony/var-dumper) to permit the latest version.
- [Release notes](https://github.com/symfony/var-dumper/releases)
- [Changelog](https://github.com/symfony/var-dumper/blob/7.1/CHANGELOG.md)
- [Commits](symfony/var-dumper@v6.2.0...v7.1.1)

---
updated-dependencies:
- dependency-name: symfony/var-dumper
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

composer.json

@@ -41,7 +41,7 @@
         "symfony/mime": "^6.2",
         "symfony/routing": "^6.2",
         "symfony/string": "^6.2",
-        "symfony/var-dumper": "^6.2",
+        "symfony/var-dumper": "^6.2 || ^7.0",
         "vlucas/phpdotenv": "^5.5",
         "voku/portable-ascii": "^2.0.1"
     },