[issues-1787] add AssumeRole op to presign generate list

.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"
+    ]
+}

codegen/smithy-aws-go-codegen/src/main/java/software/amazon/smithy/aws/go/codegen/AwsHttpPresignURLClientGenerator.java

@@ -100,7 +100,9 @@ public class AwsHttpPresignURLClientGenerator implements GoIntegration {
                     ShapeId.from("com.amazonaws.s3#DeleteBucket")
             ),
             ShapeId.from("com.amazonaws.sts#AWSSecurityTokenServiceV20110615"), SetUtils.of(
-                    ShapeId.from("com.amazonaws.sts#GetCallerIdentity"))
+                    ShapeId.from("com.amazonaws.sts#GetCallerIdentity"),
+                    ShapeId.from("com.amazonaws.sts#AssumeRole")
+            )
     );
 
     // map of service to list of operations for which presignedURL client and operation should