Upgrade php-di to 7.0, to replace deprecated usage.

[tsluyter]

The current version of php-di (6.4) has a number of deprecated features and usages which lead to errors in Slim-Skeleton.

For example, running Slim-Skeleton with PHP 8.3 gives the following trace:

Deprecated: DI\create(): Implicitly marking parameter $className as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/functions.php on line 35

Deprecated: DI\autowire(): Implicitly marking parameter $className as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/functions.php on line 48

Deprecated: DI\ContainerBuilder::writeProxiesToFile(): Implicitly marking parameter $proxyDirectory as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/ContainerBuilder.php on line 283

Deprecated: DI\Definition\Helper\CreateDefinitionHelper::__construct(): Implicitly marking parameter $className as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/Helper/CreateDefinitionHelper.php on line 56

Deprecated: DI\Definition\Source\ReflectionBasedAutowiring::autowire(): Implicitly marking parameter $definition as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/Source/ReflectionBasedAutowiring.php on line 19

Deprecated: DI\Definition\Source\Autowiring::autowire(): Implicitly marking parameter $definition as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/Source/Autowiring.php on line 23

Deprecated: DI\Definition\Source\DefinitionArray::__construct(): Implicitly marking parameter $autowiring as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/Source/DefinitionArray.php on line 39

Deprecated: DI\Definition\Source\DefinitionNormalizer::normalizeRootDefinition(): Implicitly marking parameter $wildcardsReplacements as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/Source/DefinitionNormalizer.php on line 46

Deprecated: DI\Proxy\ProxyFactory::__construct(): Implicitly marking parameter $proxyDirectory as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Proxy/ProxyFactory.php on line 43

Deprecated: DI\Container::__construct(): Implicitly marking parameter $definitionSource as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Container.php on line 97

Deprecated: DI\Container::__construct(): Implicitly marking parameter $proxyFactory as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Container.php on line 97

Deprecated: DI\Container::__construct(): Implicitly marking parameter $wrapperContainer as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Container.php on line 97

Deprecated: DI\Definition\ObjectDefinition::__construct(): Implicitly marking parameter $className as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/ObjectDefinition.php on line 72

Deprecated: DI\Definition\ObjectDefinition::setClassName(): Implicitly marking parameter $className as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/ObjectDefinition.php on line 88

Deprecated: DI\Definition\ObjectDefinition::setLazy(): Implicitly marking parameter $lazy as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/ObjectDefinition.php on line 186

Deprecated: DI\Definition\Resolver\ObjectCreator::setPrivatePropertyValue(): Implicitly marking parameter $className as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/Resolver/ObjectCreator.php on line 212

Deprecated: DI\Definition\Resolver\ParameterResolver::resolveParameters(): Implicitly marking parameter $definition as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/Resolver/ParameterResolver.php on line 38

Deprecated: DI\Definition\Resolver\ParameterResolver::resolveParameters(): Implicitly marking parameter $method as nullable is deprecated, the explicit nullable type must be used instead in /var/www/vendor/php-di/php-di/src/Definition/Resolver/ParameterResolver.php on line 38
Hello world!{ "statusCode": 500, "error": { "type": "SERVER_ERROR", "description": "FATAL ERROR: DI\\Definition\\Resolver\\ParameterResolver::resolveParameters(): Implicitly marking parameter $method as nullable is deprecated, the explicit nullable type must be used instead. on line 38 in file \/var\/www\/vendor\/php-di\/php-di\/src\/Definition\/Resolver\/ParameterResolver.php." } }

Upgrading php-di from 6.4 to 7.0 gets rid of all deprecation warnings.