build(deps-dev): update shipmonk/dead-code-detector requirement || ^0.15

Updates the requirements on [shipmonk/dead-code-detector](https://github.com/shipmonk-rnd/dead-code-detector) to permit the latest version.
- [Release notes](https://github.com/shipmonk-rnd/dead-code-detector/releases)
- [Commits](shipmonk-rnd/dead-code-detector@0.14.0...0.15.0)

---
updated-dependencies:
- dependency-name: shipmonk/dead-code-detector
  dependency-version: 0.15.0
  dependency-type: direct:development
...

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

Author: dependabot[bot]

composer.json

@@ -129,7 +129,7 @@
         "rector/swiss-knife": "^2.3",
         "rector/type-perfect": "^2.1",
         "shipmonk/composer-dependency-analyser": "^1.8",
-        "shipmonk/dead-code-detector": "^0.14",
+        "shipmonk/dead-code-detector": "^0.14 || ^0.15",
         "shipmonk/name-collision-detector": "^2.1",
         "shipmonk/phpstan-baseline-per-identifier": "^2.3",
         "shipmonk/phpstan-rules": "^4.3",