Simplify budget distribution logic and new worker metadata consumption

[m-trieu]

Remove the budget distributor thread and move the managing of each server's internal budget to the direct GetWorkStream.

R: @arunpandianp @scwhittle

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[m-trieu]

back to you @scwhittle Thanks!

[m-trieu]

thanks @scwhittle ! back to you

[scwhittle]

Run Java PreCommit

[Abacn]

It seems "FanOutStreamingEngineWorkerHarnessTest" becomes increasingly flaky recently, e.g. on schedule run:

https://github.com/apache/beam/runs/32620998299

and on a PR run:

https://github.com/apache/beam/runs/32622849052

error:

java.lang.AssertionError
	at org.junit.Assert.fail(Assert.java:87)
	at org.junit.Assert.assertTrue(Assert.java:42)
	at org.junit.Assert.assertTrue(Assert.java:53)
	at org.apache.beam.runners.dataflow.worker.streaming.harness.FanOutStreamingEngineWorkerHarnessTest.testStreamsStartCorrectly(FanOutStreamingEngineWorkerHarnessTest.java:217)