Apply suggestion from @chr-hertel

Author: chr-hertel

CONTRIBUTING.md

@@ -43,11 +43,6 @@ make conformance-tests   # requires Docker
 This project follows [Symfony's coding standards](https://symfony.com/doc/current/contributing/code/standards.html)
 and [backward compatibility promise](https://symfony.com/doc/current/contributing/code/bc.html). In short:
 
-- Type hints on every parameter and return value.
-- Final classes by default — only leave a class non-final when it's deliberately designed for extension.
-- Prefer immutable value objects.
-- DocBlocks explain *why*, not *what* — the code and its types should already say what it does.
-
 See [CLAUDE.md](CLAUDE.md) for a fuller tour of the codebase's architecture and layout.
 
 ## Tests