Remove AttributesSniff to fix conflict with Slevomat ReferenceUsedNamesOnly

[dereuromark]

Summary

• Remove PhpCollective\Sniffs\Commenting\AttributesSniff which required FQCN for PHP 8 attributes
• Remove associated test files

Problem

The AttributesSniff required fully qualified class names (FQCN) for PHP 8 attributes, e.g.:

#[\PHPUnit\Framework\Attributes\DataProvider('foo')]

However, this conflicts with SlevomatCodingStandard.Namespaces.ReferenceUsedNamesOnly which requires using short names via use statements:

use PHPUnit\Framework\Attributes\DataProvider;

#[DataProvider('foo')]

When both rules are active, phpcbf enters an infinite loop:

1. AttributesSniff converts to FQCN
2. ReferenceUsedNamesOnly converts back to short name with use statement
3. Go to step 1

Solution

Remove the AttributesSniff to resolve this conflict. This aligns with the modern PHP convention of using short names with use statements for better:

• Readability
• IDE support (refactoring, find usages)
• Consistency with the rest of the codebase

Test plan

• Verify no infinite loop when running phpcs/phpcbf on files with PHP 8 attributes
• Run existing test suite

🤖 Generated with Claude Code