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### _Why are the changes needed?_
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Allow the engine not to self-terminate. For details: #1472.
### _How was this patch tested?_
- [ ] 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#1475 from wForget/KYUUBI-1472.
Closes#1472
97412e54 [Wang Zhen] Merge remote-tracking branch 'remotes/origin/master'
8ff0cf72 [Wang Zhen] [KYUUBI-1472] allow the engine not to self-terminate. Use zero or negative to represent no limit.
7cfa03c1 [Wang Zhen] [KYUUBI-1472] allow the engine not to self-terminate.
Authored-by: Wang Zhen <wangzhen07@qiyi.com>
Signed-off-by: ulysses-you <ulyssesyou@apache.org>
cc40c87743