Drianer can't start with configuration syncer.to.checkpoint.schema contains "-"

[cyliu0]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. What did you do?
   If possible, provide a recipe for reproducing the error.
   Use tiup to deploy tidb binlog with configuration syncer.to.checkpoint.schema = "tidb-binlog" like https://github.com/pingcap/docs-cn/blob/81c4ca1e36b1ce05e27a4b8d93c465119f547b1c/config-templates/complex-tidb-binlog.yaml#L132

Detailed information refers to https://asktug.com/t/topic/574516

2. What did you expect to see?
   Drainers start properly

3. What did you see instead?
   Drainers cannot start

4. Please provide the relate downstream type and version of drainer.
   (run drainer -V in terminal to get drainer's version)