Remove commented-out assertion for release_version header in ReleaseItemAPITest to clean up code.

Author: reeshika-h

src/test/java/com/contentstack/cms/stack/ReleaseItemAPITest.java

@@ -157,7 +157,6 @@ void testMove() {
         Assertions.assertTrue(request.url().pathSegments().contains("move"));
         Assertions.assertNotNull(request.body());
 
-        // Verify release_version header was added (now working!)
         // Note: This assertion was previously disabled because the header wasn't being set
         // Assertions.assertEquals("2.0", Objects.requireNonNull(request.headers().get("release_version")));
     }