Update twig/twig requirement from ^3.7 to ^3.8

Updates the requirements on [twig/twig](https://github.com/twigphp/Twig) to permit the latest version.
- [Changelog](https://github.com/twigphp/Twig/blob/3.x/CHANGELOG)
- [Commits](twigphp/Twig@v3.7.0...v3.8.0)

---
updated-dependencies:
- dependency-name: twig/twig
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

composer.json

@@ -21,7 +21,7 @@
         "php": "^7.4 || ^8.0",
         "psr/http-message": "^1.1",
         "slim/slim": "^4.12",
-        "twig/twig": "^3.7",
+        "twig/twig": "^3.8",
         "symfony/polyfill-php81": "^1.28"
     },
     "require-dev": {