Add changelog entry

Author: zoewangg

.changes/next-release/feature-AWSSDKforJavav2-5b21f76.json

@@ -0,0 +1,6 @@
+{
+    "type": "feature",
+    "category": "AWS SDK for Java v2",
+    "contributor": "",
+    "description": "Add support for additional checksum algorithms: XXHASH64, XXHASH3, XXHASH128, SHA512."
+}