[MINOR] Adding back PRECOMBINE_FIELD Config property in DataSourceReadOptions

[nsivabalan]

Change Logs

Adding back PRECOMBINE_FIELD Config property in DataSourceReadOptions. When we renamed the precombine field
#13718 here, we removed the config property. This could be used by users in their pipeline scripts for setting writer properties. atleast this is one of the 3 basic properties for creating a hudi table.

Impact

Existing user scripts will not break.

Risk level (write none, low medium or high below)

low

Documentation Update

Describe any necessary documentation update if there is any new feature, config, or user-facing change. If not, put "none".

• The config description must be updated if new configs are added or the default value of the configs are changed
• Any new feature or user-facing change requires updating the Hudi website. Please create a Jira ticket, attach the
  ticket number here and follow the instruction to make
  changes to the website.

Contributor's checklist

• Read through contributor's guide
• Change Logs and Impact were stated clearly
• Adequate tests were added if applicable
• CI passed

[hudi-bot]

CI report:

• 4ee7c35 Azure: FAILURE

Bot commands

@hudi-bot supports the following commands:

• @hudi-bot run azure re-run the last Azure build

[jonvex]

lgtm