allow it to be calculated, just by pass the calculation

Author: TingDaoK

source/s3_request_messages.c

@@ -838,8 +838,9 @@ static int s_calculate_in_memory_checksum_helper(
     struct aws_byte_cursor data,
     struct aws_s3_upload_request_checksum_context *checksum_context) {
     AWS_ASSERT(checksum_context);
-    AWS_ASSERT(!checksum_context->checksum_calculated);
-    AWS_ASSERT(checksum_context->algorithm != AWS_SCA_NONE);
+    if (checksum_context->checksum_calculated) {
+        return AWS_OP_SUCCESS;
+    }
 
     int ret_code = AWS_OP_ERR;
     /* Calculate checksum for output buffer only (no header/trailer) */