[Doc] [connectors-v2] [Http Source] Http source option key poll_interval_ms different in source code

[Zhouwen-CN]

#5429

Purpose of this pull request

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.

[liunaijie]

i think it's better update the document not the code.

[zhilinli123]

i think it's better update the document not the code.
+1

[Zhouwen-CN]

@liunaijie
@zhilinli123
PTAL

[zhilinli123]

Good , wait CI