[Improve][connector-file] unifiy option between file source/sink and update document

[liunaijie]

Purpose of this pull request

close #5461 and #4572

1. unified option in file source/sink (source parameter delimiter update to field_delimiter)
2. update the doucment
   a) update parameter name
   b) refactor docs using unified format

Does this PR introduce any user-facing change?

yes, the file source paramter delimiter updated to field_delimiter to keep same with sink paramter

How was this patch tested?

use e2e

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 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.

[Hisoka-X]

So after this PR, seem like delimiter will not worked. This is unacceptable and will hinder users who need to upgrade. If we need to modify a configuration key, we should be compatible with the old configuration at the same time.

[Hisoka-X]

So I think you should answer this question.

Also please update the title.

[Hisoka-X]

Could you add a test case for old config key delimiter? We should make sure the delimiter work fine too after this change.

[Hisoka-X]

The test case seem like can not prove the delimiter is ":". Could you add a rule to check row value? You can refer https://github.com/apache/seatunnel/pull/5083/files#diff-a68b2797462655fd5ee139c5c129df223f4de9c25e72e41a6432012d00ede0a8

[Hisoka-X]

Thanks @liunaijie .Waiting CI pass.