config, scheduler(ticdc): add MaxTableCount and AddTableBatchSize to ChangefeedSchedulerConfig

[CharlesCheung96]

What problem does this PR solve?

Issue Number: close #11216

What is changed and how it works?

1. Move AddTableBatchSize from server to changefeed config.
2. Add MaxTableCount to limit the max tables for each capture to avoid unbalance.
3. Auto adjust batchSize in scheduler_basic if AddTableBatchSize=0. And the adjustment range is 50 to 1000.

Check List

Tests

• Manual test (add detailed scripts or steps below)

• Before this PR: The schedule has not been completed in 40 minutes.

• This PR: The scheduling was completed in 10min

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

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