The default values of `logger.size` and `logger.count` for the TiFlash configuration file parameters are incorrect.

[fzzf678]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. What did you do?

The default value of the logger.size parameter in the TiFlash configuration file is incorrect, the actual default value is 1000M. The default value of logger.count is incorrect, the actual default value is 20. https://docs.pingcap.com/tidb/stable/tiflash-configuration/#logger

2. What did you expect to see?
   The default values are consistent with doc

3. What did you see instead?
   Inconsistent

4. What version of TiUP are you using (tiup --version)?
   master