Update orchestra/testbench requirement from ^6.23.1 to ^6.23.2

Updates the requirements on [orchestra/testbench](https://github.com/orchestral/testbench) to permit the latest version.
- [Release notes](https://github.com/orchestral/testbench/releases)
- [Changelog](https://github.com/orchestral/testbench/blob/6.x/CHANGELOG-6.x.md)
- [Commits](orchestral/testbench@v6.23.1...v6.23.2)

---
updated-dependencies:
- dependency-name: orchestra/testbench
  dependency-type: direct:development
...

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

composer.json

@@ -29,7 +29,7 @@
     },
     "require-dev": {
         "mockery/mockery": "^1.4",
-        "orchestra/testbench": "^6.23.1"
+        "orchestra/testbench": "^6.23.2"
     },
     "config": {
         "sort-packages": true