[Build] Remove connector/seatunnel directory

[Hisoka-X]

Purpose of this pull request

This PR remove connector/seatunnel directory in binary package. Move all connector to connector directory. Because we only have one series connector.

Tested in local, also if CI passed means change work fine.

Check list

• Code changed are covered with tests, or it does not need tests for reason:
• 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 change log that in connector document. For more details you can refer to connector-v2
  2. Update plugin-mapping.properties and add new connector information in it
  3. Update the pom file of seatunnel-dist
• Update the release-note.

[hailin0]

update bin/install-plugin.sh?

[Hisoka-X]

update bin/install-plugin.sh?

oh, I forgot it. Thanks for remind.

[ruanwenjun]

update bin/install-plugin.sh?

update bin/install-plugin.cmd

[Hisoka-X]

update bin/install-plugin.sh?

update bin/install-plugin.cmd

Done

[ruanwenjun]

LGTM