BAEL-4969: Improvement: Streams to Immutable Collections (#11026)

* add new module for java core 16

* format pom.xml

core-java-modules/core-java-16/src/test/java/com/baeldung/streams/StreamToImmutableUnitTest.java

@@ -0,0 +1,23 @@
+package com.baeldung.streams;
+
+import java.util.List;
+import java.util.stream.Stream;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class StreamToImmutableUnitTest {
+
+    @Test
+    public void whenUsingStreamToList_thenReturnImmutableList() {
+
+        List<String> immutableList = Stream.of("a", "b", "c", "d")
+            .toList();
+
+        Assertions.assertThrows(UnsupportedOperationException.class, () -> {
+            immutableList.add("e");
+        });
+
+    }
+
+}