Modify the optimizer to support obtaining tasks from each AMS node for processing.

[wardlican]

Why are the changes needed?

In master-slave mode, the optimizer needs to support pulling optimization tasks from each ams node for processing.

Close #3928.

Brief change log

1. In master-slave mode, the optimizer can pull tasks from each currently active AMS.
2. In master-slave mode, the AMS automatically detects the addition and timeout of the optimizer from the database.

How was this patch tested?

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

• [ ] Add screenshots for manual tests if appropriate

• [x] 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)