added config definition for cache enabler

src/DependencyInjection/Configuration.php

@@ -29,6 +29,12 @@ final class Configuration implements ConfigurationInterface
                     ->end()
                     ->arrayNode('cache')
                         ->children()
+                            ->booleanNode('enabled')
+                                ->info('Enable/disable cache')
+                                ->defaultTrue()
+                                ->cannotBeEmpty()
+                                ->isRequired()
+                            ->end()
                             ->scalarNode('ttl')
                                 ->info('TTL for cached API calls')
                                 ->example([1800, 'P30M'])