UPdated to be compatible with PHPStan level 9

Author: gplanchat

.github/workflows/phpstan-6.yaml

@@ -34,5 +34,5 @@ jobs:
         uses: php-actions/phpstan@v3
         with:
           path: src/
-          level: 5
+          level: 9
           php_version: '8.2'

.github/workflows/phpstan-7.yaml

@@ -4,12 +4,7 @@ Pipeline contracts
 This package brings interfaces for the pipeline component, aimed at providing an Extract-Transform-Load pattern,
 with logging, line rejections and execution states.
 
-
-[![Quality](https://github.com/php-etl/pipeline-contracts/actions/workflows/quality.yaml/badge.svg)](https://github.com/php-etl/pipeline-contracts/actions/workflows/quality.yaml)
-[![PHPStan level 5](https://github.com/php-etl/pipeline-contracts/actions/workflows/phpstan-5.yaml/badge.svg)](https://github.com/php-etl/pipeline-contracts/actions/workflows/phpstan-5.yaml)
-[![PHPStan level 6](https://github.com/php-etl/pipeline-contracts/actions/workflows/phpstan-6.yaml/badge.svg)](https://github.com/php-etl/pipeline-contracts/actions/workflows/phpstan-6.yaml)
-[![PHPStan level 7](https://github.com/php-etl/pipeline-contracts/actions/workflows/phpstan-7.yaml/badge.svg)](https://github.com/php-etl/pipeline-contracts/actions/workflows/phpstan-7.yaml)
-[![PHPStan level 8](https://github.com/php-etl/pipeline-contracts/actions/workflows/phpstan-8.yaml/badge.svg)](https://github.com/php-etl/pipeline-contracts/actions/workflows/phpstan-8.yaml)
+[![Quality (PHPStan level 9)](https://github.com/php-etl/pipeline-contracts/actions/workflows/quality.yaml/badge.svg)](https://github.com/php-etl/pipeline-contracts/actions/workflows/quality.yaml)
 ![PHP](https://img.shields.io/packagist/php-v/php-etl/pipeline-contracts)
 
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