fix deprecated code

See issue #235

Author: garak

src/DependencyInjection/Configuration.php

@@ -21,7 +21,7 @@ class Configuration implements ConfigurationInterface
      * @throws \InvalidArgumentException
      * @throws \RuntimeException
      */
-    public function getConfigTreeBuilder()
+    public function getConfigTreeBuilder(): TreeBuilder
     {
         $treeBuilder = new TreeBuilder('sentry');
         /** @var ArrayNodeDefinition $rootNode */

src/DependencyInjection/SentryExtension.php

@@ -32,7 +32,7 @@ class SentryExtension extends Extension
      *
      * @throws InvalidConfigurationException
      */
-    public function load(array $configs, ContainerBuilder $container)
+    public function load(array $configs, ContainerBuilder $container): void
     {
         $configuration = new Configuration();
         $processedConfiguration = $this->processConfiguration($configuration, $configs);