chore(deps): update dependency orchestra/testbench to v7.15.0 (#48)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

composer.json

@@ -18,7 +18,7 @@
     "illuminate/support": "^9.3",
     "mockery/mockery": "1.5.1",
     "nunomaduro/phpinsights": "2.6.1",
-    "orchestra/testbench": "7.11.0",
+    "orchestra/testbench": "7.15.0",
     "pestphp/pest": "1.22.1",
     "pestphp/pest-plugin-parallel": "1.2.0",
     "phpunit/phpunit": "9.5.25"