[AMORO-3066] Optimizing the efficiency for optimizing-processes rest api

[klion26]

Why are the changes needed?

Close #3066.

Brief change log

• remove the ServerCatalog#tableExists(db, table) in TableController#getOptimizingProcesses because we can reuse the table load logic in the following logic
• push the offset and limit in mapper#selectOptimizingProcesses(MixedAndIcebergTableDescriptor#getOptimizingProcessesInfo) to db (this can limit the items retrieved from db)

How was this patch tested?

• Add some test cases that check the changes thoroughly including negative and positive cases if possible

• Add screenshots for manual tests if appropriate

• Run test locally before making a pull request
  
  

Documentation

• Does this pull request introduce a new feature? (yes / no)
• If yes, how is the feature documented? (not applicable / docs / JavaDocs / not documented)

[klion26]

@zhoujinsong @majin1102 could you please have a look when you're free thanks.

[zhoujinsong]

Thanks for the work!
I left some comments, PTAL.

[majin1102]

LGTM

Thanks for this contribution.

[zhoujinsong]

LGTM and validated in my local envirionment.
Thanks for the work! @klion26

[klion26]

thanks for the review and merging! @zhoujinsong @majin1102