fix autolabeler by adding permissions and pull requests events

[shenxianpeng]

Right now we have supported autolabeler

.github/.github/release-drafter.yml

Lines 75 to 88 in b7268d7

	autolabeler:
	- label: 'documentation'
	files:
	- '*.md'
	branch:
	- '/docs{0,1}\/.+/'
	- label: 'bug'
	branch:
	- '/fix\/.+/'
	title:
	- '/fix/i'
	- label: 'enhancement'
	branch:
	- '/feature\/.+/'

but it doesn't work actually. from the docs https://github.com/toolmantim/release-drafter we need to

• add permission to b7268d7
• add pull request events to workflow. e.g.: fix autolabeler by adding pull request events cpp-linter-hooks#41

[2bndy5]

Also add rst files for Sphinx docs

     files: 
       - '*.md' 
       - '*.rst'