Problem: EnhancedExecutionStrategyProvider is not injected in OSGi

Solution: declare it as a component

Author: yrashk

src/main/java/graphql/servlet/EnhancedExecutionStrategyProvider.java

@@ -16,7 +16,9 @@
 
 import graphql.annotations.EnhancedExecutionStrategy;
 import graphql.execution.ExecutionStrategy;
+import org.osgi.service.component.annotations.Component;
 
+@Component(property = "type=enhanced")
 public class EnhancedExecutionStrategyProvider implements ExecutionStrategyProvider {
     @Override
     public ExecutionStrategy getExecutionStrategy() {