Fix "Definition could not be converted to string" error

[sadikoff]

This will fix #845

@nicolas-grekas Can you confirm that this code will work as expected?

[nicolas-grekas]

Would you be able to provide me with a reproducer? I'd like to see what this Definition is about.

[sadikoff]

Configured for php7.4 https://github.com/sadikoff/maker-bundle-bug-reproducer
Steps:

1. Install dependencies symfony composer install
2. Try to install maker symfony composer require maker
   Error

Executing script cache:clear [KO]
[KO]
Script cache:clear returned with error code 255
!! Error {#3158
!! #message: "Object of class Symfony\Component\DependencyInjection\Definition could not be converted to string"
!! #code: 0
!! #file: "./vendor/symfony/maker-bundle/src/DependencyInjection/CompilerPass/SetDoctrineAnnotatedPrefixesPass.php"
!! #line: 41
!! trace: {
!! ./vendor/symfony/maker-bundle/src/DependencyInjection/CompilerPass/SetDoctrineAnnotatedPrefixesPass.php:41 { …}
!! ./vendor/symfony/dependency-injection/Compiler/Compiler.php:91 { …}
!! ./vendor/symfony/dependency-injection/ContainerBuilder.php:736 { …}
!! ./vendor/symfony/http-kernel/Kernel.php:541 { …}
!! ./vendor/symfony/http-kernel/Kernel.php:780 { …}
!! ./vendor/symfony/http-kernel/Kernel.php:121 { …}
!! ./vendor/symfony/framework-bundle/Console/Application.php:168 { …}
!! ./vendor/symfony/framework-bundle/Console/Application.php:74 { …}
!! ./vendor/symfony/console/Application.php:166 { …}
!! ./bin/console:43 {
!! › $application = new Application($kernel);
!! › $application->run($input);
!! ›
!! arguments: {
!! $input: Symfony\Component\Console\Input\ArgvInput {#5 …}
!! }
!! }
!! }
!! }
!! 2021-03-23T09:37:07+00:00 [critical] Uncaught Error: Object of class Symfony\Component\DependencyInjection\Definition could not be converted to string
!!
Script @auto-scripts was called via post-update-cmd

PS @nicolas-grekas be sure to pull the latest changes from the reproducer 😃

[nicolas-grekas]

Thanks for the PR and the reproducer, I created #847 instead.