Add changelog entry

Author: zoewangg

.changes/next-release/feature-AWSSDKforJavav2Codegen-7921896.json

@@ -0,0 +1,6 @@
+{
+    "type": "feature",
+    "category": "AWS SDK for Java v2 Codegen",
+    "contributor": "",
+    "description": "Automatically enable `AwsV4HttpSigner.CHUNK_ENCODING_ENABLED` signer property for input streaming operations that support checksums in generated auth scheme provider class"
+}