[Fix][Command] Run seatunnel on windows with fileAppender enabled, no log file been created

[FrommyMind]

Purpose of this pull request

Fix #8929

Does this PR introduce any user-facing change?

No

How was this patch tested?

Check list

• If any new Jar binary package adding in your PR, please add License Notice according
  New License Guide
• If necessary, please update the documentation to describe the new feature. https://github.com/apache/seatunnel/tree/dev/docs
• If you are contributing the connector code, please check that the following files are updated:
  1. Update plugin-mapping.properties and add new connector information in it
  2. Update the pom file of seatunnel-dist
  3. Add ci label in label-scope-conf
  4. Add e2e testcase in seatunnel-e2e
  5. Update connector plugin_config
• Update the release-note.

Tested on my local windows pc.
After enable fileAppender in log4j2_client.properties. client log have been created.

[Hisoka-X]

Could you help verify it? @hawk9821

[hailin0]

LGTM

[FrommyMind]

Update the logic of get filename. May fix this #8226 (comment)