Removed casted Function for lambda. Fixes 201. (#202)

Author: jcustenborder

connect-utils-testing/src/main/java/com/github/jcustenborder/kafka/connect/utils/templates/PluginLoader.java

@@ -17,7 +17,6 @@
 
 
 import com.github.jcustenborder.kafka.connect.utils.config.ConfigKeyComparator;
-import com.google.common.base.Function;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableSet;
 import org.apache.kafka.common.config.ConfigDef;
@@ -226,7 +225,7 @@ Plugin.Configuration config(Class<?> pluginClass) {
           .validator(configKey.validator)
           .build();
 
-      ImmutableGroup.Builder groupBuilder = groupBuilderCache.computeIfAbsent(group, (Function<String, ImmutableGroup.Builder>) s -> ImmutableGroup.builder().name(group));
+      ImmutableGroup.Builder groupBuilder = groupBuilderCache.computeIfAbsent(group, s -> ImmutableGroup.builder().name(group));
       groupBuilder.addItems(item);
       if (item.isRequired()) {
         configBuilder.addRequiredConfigs(item);