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### _Why are the changes needed?_
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Fix some issues:
1. EngineServiceDiscovery calls deregister twice
2. When LOST zk-server, the delay for gracefully stop shall be calculated via retry policy not retrywait * maxWaitMs
- engine default using n time retry policy, we can avoid unnecessary cache for engines when the whole test file finished and server stopped
- otherwise, we are very likey to hit the GA memory limits
```
KyuubiOperationPerGroupSuite:
./build/mvn: line 99: 1725 Killed ${MVN_BIN} $MAVEN_CLI_OPTS "$"
Error: Process completed with exit code 137.
```
3. When LOST, we shall skip connection retries, closing znode & closingclient
### _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](https://kyuubi.readthedocs.io/en/latest/develop_tools/testing.html#running-tests) locally before make a pull request
Closes#1785 from yaooqinn/stop.
Closes#1785
afdd4b47 [Kent Yao] Stop Discovery services properly
5efa493a [Kent Yao] Stop Discovery services properly
45f9312e [Kent Yao] Stop Discovery services properly
d899012e [Kent Yao] Stop Discovery services properly
925ff3e9 [Kent Yao] Stop Discovery services properly
1f766116 [Kent Yao] Stop Discovery services properly
0d25f6a1 [Kent Yao] Stop Discovery services properly
ff833751 [Kent Yao] Stop Discovery services properly
55d64c02 [Kent Yao] Stop Discovery services properly
Authored-by: Kent Yao <yao@apache.org>
Signed-off-by: ulysses-you <ulyssesyou@apache.org>
3aba64d9bb