Added project initializability check in docker-entrypoint.sh

[7-zete-7]

Currently, if there are errors that prevent the project from initializing correctly, the php container console shows a database connection error (see #718).

With this PR, I propose adding a check to ensure that the project can be initialized before checking the database connection. This will allow you to see a specific error in the php container console.

[7-zete-7]

So far I've come up with the idea to use version retrieval.

When using the version retrieval command

bin/console -V

It will output either project version information

Symfony 6.4.16 (env: dev, debug: true)

Or error information

ParseError {#2236
  #message: "syntax error, unexpected identifier "p", expecting "function""
  #code: 0
  #file: "./src/SomethingBroken.php"
  #line: 23
  trace: {
    ./src/SomethingBroken.php:23 {
      Composer\Autoload\{closure}^
      › {
      ›     p rivate string $foobar;
      ›
    }
    ./vendor/composer/ClassLoader.php:427 { …}
    ./vendor/symfony/error-handler/DebugClassLoader.php:300 { …}
    Symfony\Component\ErrorHandler\DebugClassLoader->loadClass() {}
    ./vendor/symfony/config/Resource/ClassExistenceResource.php:76 { …}
    ./vendor/symfony/dependency-injection/ContainerBuilder.php:361 { …}
    ./vendor/symfony/dependency-injection/Loader/FileLoader.php:293 { …}
    ./vendor/symfony/dependency-injection/Loader/FileLoader.php:121 { …}
    ./vendor/symfony/dependency-injection/Loader/YamlFileLoader.php:706 { …}
    ./vendor/symfony/dependency-injection/Loader/YamlFileLoader.php:254 { …}
    ./vendor/symfony/dependency-injection/Loader/YamlFileLoader.php:177 { …}
    ./vendor/symfony/dependency-injection/Loader/YamlFileLoader.php:133 { …}
    ./vendor/symfony/config/Loader/FileLoader.php:167 { …}
    ./vendor/symfony/config/Loader/FileLoader.php:98 { …}
    ./vendor/symfony/dependency-injection/Loader/FileLoader.php:70 { …}
    ./vendor/symfony/dependency-injection/Loader/Configurator/ContainerConfigurator.php:64 { …}
    ./vendor/symfony/framework-bundle/Kernel/MicroKernelTrait.php:57 { …}
    ./vendor/symfony/framework-bundle/Kernel/MicroKernelTrait.php:190 { …}
    ./vendor/symfony/dependency-injection/Loader/ClosureLoader.php:36 { …}
    ./vendor/symfony/config/Loader/DelegatingLoader.php:37 { …}
    ./vendor/symfony/framework-bundle/Kernel/MicroKernelTrait.php:146 { …}
    ./vendor/symfony/http-kernel/Kernel.php:616 { …}
    ./vendor/symfony/http-kernel/Kernel.php:505 { …}
    ./vendor/symfony/http-kernel/Kernel.php:771 { …}
    ./vendor/symfony/http-kernel/Kernel.php:126 { …}
    ./src/Kernel.php:82 { …}
    ./vendor/symfony/framework-bundle/Console/Application.php:190 { …}
    ./vendor/symfony/framework-bundle/Console/Application.php:72 { …}
    ./vendor/symfony/console/Application.php:175 { …}
    ./vendor/symfony/runtime/Runner/Symfony/ConsoleApplicationRunner.php:49 { …}
    ./vendor/autoload_runtime.php:29 { …}
    ./bin/console:15 { …}
  }
}