Fix unit test

Author: oliemansm

graphql-webclient/src/test/java/graphql/kickstart/spring/webclient/boot/GraphQLWebClientTest.java

@@ -8,7 +8,6 @@
 import com.fasterxml.jackson.databind.ObjectMapper;
 import graphql.kickstart.spring.webclient.testapp.Simple;
 import java.util.List;
-import java.util.Map;
 import java.util.Optional;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;

graphql-webclient/src/test/java/graphql/kickstart/spring/webclient/boot/Map.java

@@ -0,0 +1,13 @@
+package graphql.kickstart.spring.webclient.boot;
+
+import java.util.HashMap;
+
+class Map {
+
+  static java.util.Map<String,Object> of(String key, String value) {
+    java.util.Map<String,Object> map = new HashMap<>();
+    map.put(key, value);
+    return map;
+  }
+
+}