Update dependency composer/composer to ^2.9.6 [SECURITY]

| datasource | package           | from  | to    |
| ---------- | ----------------- | ----- | ----- |
| packagist  | composer/composer | 2.9.5 | 2.9.6 |

Author: renovate[bot]

composer.json

@@ -20,7 +20,7 @@
         "php-standard-library/file": "^6.0",
         "php-standard-library/vec": "^6.0",
         "php-standard-library/shell": "^6.0",
-        "composer/composer": "^2.9.5",
+        "composer/composer": "^2.9.6",
         "nikic/php-parser": "^5.7.0",
         "nikolaposa/version": "^4.2.1",
         "ocramius/package-versions": "^2.11.0",