[HUDI-9022] Handle records with custom delete markers for MOR

[linliu-code]

Change Logs

Log data block may contain delete records labelled by the custom delete marker.
Currently these records will go through the non-delete record process path.
This PR identifies these records in the fg reader, and process them as normal delete records.

Impact

Support custom delete records for MOR table.

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:

• 9c54e64 UNKNOWN
• 0314fa6 UNKNOWN
• 2eacf85 Azure: SUCCESS

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