### What changes were proposed in this pull request?
Add config to limit max workers when offering slots, the config can be set both
in server side and client side. Celeborn will choose the smaller positive configs from client and master.
### Why are the changes needed?
For large Celeborn clusters, users may want to limit the number of workers that
a shuffle can spread, reasons are:
1. One worker failure will not affect all applications
2. One huge shuffle will not affect all applications
3. It's more efficient to limit a shuffle within a restricted number of workers, say 100, than
spreading across a large number of workers, say 1000, because the network connections
in pushing data is `number of ShuffleClient` * `number of allocated Workers`
The recommended number of Workers should depend on workload and Worker hardware,
and this can be configured per application, so it's relatively flexible.
### Does this PR introduce _any_ user-facing change?
No, added a new configuration.
### How was this patch tested?
Added ITs and passes GA.
Closes#1790 from waitinfuture/152.
Authored-by: zky.zhoukeyong <zky.zhoukeyong@alibaba-inc.com>
Signed-off-by: zky.zhoukeyong <zky.zhoukeyong@alibaba-inc.com>
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