docs(commons): link Stream

commons/src/main/java/io/gitlab/jfronny/commons/StreamUtil.java

@@ -2,11 +2,12 @@ package io.gitlab.jfronny.commons;
 
 import java.util.function.BiConsumer;
 import java.util.function.Consumer;
+import java.util.stream.Stream;
 
 public class StreamUtil {
     /**
      * A BiConsumer that keeps only elements of the specified type.
-     * To be used with Stream.mapMulti.
+     * To be used with {@link Stream}.mapMulti.
      *
      * @param type The type to keep
      * @param <E> The type of the elements