Fix CollectionUtil toSeq methods

Signed-off-by: Matthew de Detrich <mdedetrich@gmail.com>

stream/src/main/scala-2.12/org/apache/pekko/stream/javadsl/CollectionUtil.scala

@@ -21,6 +21,7 @@ package javadsl
 import scala.collection.immutable
 
 import org.apache.pekko
+import pekko.annotation.InternalApi
 import pekko.japi.Util.immutableSeq
 
 /**
@@ -28,6 +29,7 @@ import pekko.japi.Util.immutableSeq
  *
  * Utility methods for converting Java collections to Scala collections.
  */
+@InternalApi
 private[javadsl] object CollectionUtil {
   @inline def toSeq[T](jlist: java.util.List[T]): immutable.Seq[T] =
     immutableSeq(jlist)

stream/src/main/scala-2.13/org/apache/pekko/stream/javadsl/CollectionUtil.scala

@@ -21,6 +21,7 @@ package javadsl
 import scala.collection.immutable
 
 import org.apache.pekko
+import pekko.annotation.InternalApi
 import pekko.util.ccompat.JavaConverters._
 
 /**
@@ -28,6 +29,7 @@ import pekko.util.ccompat.JavaConverters._
  *
  * Utility methods for converting Java collections to Scala collections.
  */
+@InternalApi
 private[javadsl] object CollectionUtil {
   @inline def toSeq[T](jlist: java.util.List[T]): immutable.Seq[T] =
     jlist.asScala.toSeq

stream/src/main/scala-3/org/apache/pekko/stream/javadsl/CollectionUtil.scala

@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.pekko.stream
+package javadsl
+
+import scala.collection.immutable
+
+import org.apache.pekko
+import pekko.annotation.InternalApi
+import pekko.util.ccompat.JavaConverters._
+
+/**
+ * INTERNAL API
+ *
+ * Utility methods for converting Java collections to Scala collections.
+ */
+@InternalApi
+private[javadsl] object CollectionUtil {
+  inline def toSeq[T](jlist: java.util.List[T]): immutable.Seq[T] =
+    jlist.asScala.toSeq
+
+  inline def toSeq[T](jiterable: java.lang.Iterable[T]): immutable.Seq[T] =
+    jiterable.asScala.toSeq
+}