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### _Why are the changes needed?_
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Add some git and github steps at contribution guidelines docs. Assuming most user in github has not experience with submit pull request. And this docs make things easy for new developer.
Closes#533 from ulysses-you/improve-contribution-guidelines.
Closes#533
ce116d2 [ulysses-you] nit
d70b322 [ulysses-you] fix
70fb548 [ulysses-you] docs
Authored-by: ulysses-you <ulyssesyou18@gmail.com>
Signed-off-by: ulysses-you <ulyssesyou18@gmail.com>
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### _Why are the changes needed?_
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Refactor the key words after repo renamed.
### _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
- [ ] [Run test](https://kyuubi.readthedocs.io/en/latest/tools/testing.html#running-tests) locally before make a pull request
