added changelog file

Author: isaiahvita

.changelog/3d0e99b328234ac884bc58cfed344b21.json

@@ -0,0 +1,8 @@
+{
+    "id": "3d0e99b3-2823-4ac8-84bc-58cfed344b21",
+    "type": "feature",
+    "description": "Add presign functionality for sts:AssumeRole operation",
+    "modules": [
+        "service/sts"
+    ]
+}