Fix: se7enxweb vendor path for GraphQL type mapping
Problem
PACKAGE_DIR_PATH was hardcoded to /vendor/ezsystems/ezplatform-graphql but the package is now installed at /vendor/se7enxweb/ezplatform-graphql.
This caused GraphQL type files (e.g. FieldDefinition.types.yaml) to not be found at runtime, breaking the DI container compilation with:
Type "FieldDefinition" inherited by "ContentQueryFieldDefinition" not found.
Fix
Changed PACKAGE_DIR_PATH constant in EzSystemsEzPlatformGraphQLExtension to use the correct se7enxweb vendor path.