Doesn't work table insert sample with comments

[kotaroyamazaki]

When I tried to create a table as per the readme, I could not do it due to an encoding error in the comment section.

When I erased the comments and ran it again, it worked fine.
Is there something wrong with my settings or need to fix cooment or readme?

$ gcloud spanner databases ddl update {db-name} --instance={instance-name} --ddl-file=schemas/single_table.sql
ERROR: (gcloud.spanner.databases.ddl.update) INVALID_ARGUMENT: Error parsing Spanner DDL statement: /*\nCopyright 2022 Google LLC\n\nLicensed under the Apache License, Version 2.0 (the \"License\") : Syntax error on line 1, column 1: Encountered \'/\' while parsing: ddl_statement
- '@type': type.googleapis.com/google.rpc.LocalizedMessage
  locale: en-US
  message: |-
    Error parsing Spanner DDL statement: /*
    Copyright 2022 Google LLC

    Licensed under the Apache License, Version 2.0 (the "License") : Syntax error on line 1, column 1: Encountered '/' while parsing: ddl_statement