[KYUUBI #1548] Get docs version from project.version

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### _Why are the changes needed?_
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Fix the docs version issue

### _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 #1548 from turboFei/docs_version.

Closes #1548

dfee7b6 [Fei Wang] Fix docs version

Authored-by: Fei Wang <fwang12@ebay.com>
Signed-off-by: Fei Wang <fwang12@ebay.com>

Author: turboFei

docs/conf.py

@@ -32,6 +32,7 @@
 import os
 import sys
 import shlex
+import subprocess
 
 sys.path.insert(0, os.path.abspath('.'))
 
@@ -72,7 +73,7 @@
 author = 'Kent Yao'
 
 # The full version, including alpha/beta/rc tags
-release = '1.3.0'
+release = subprocess.getoutput("cd .. && build/mvn help:evaluate -Dexpression=project.version|grep -v Using|grep -v INFO|grep -v WARNING|tail -n 1").split('\n')[-1]
 
 
 # -- General configuration ---------------------------------------------------