[HUDI-7556] Fixing MDT validator and adding tests

[nsivabalan]

Change Logs

There is a chance that MDT could list additional partitions when compared to FS based listing.

Reason:
We load active timeline from metaclient and poll FS based listing for completed commits. And then we poll MDT for list of all partitions. in between these two, there could be a commit that could have been completed and hence MDT could be serving that as well. So, lets account for that in our validation tool

Impact

We may have false positive validation failures from MDT validators

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:

• 8e3a3c8 Azure: SUCCESS

Bot commands

@hudi-bot supports the following commands:

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