filter_multiline: Reset group metadata buf on flush - Fixes 9262,8925,9337,8567 #10913

	name: 'Pull requests commit messages'
	on:
	pull_request:
	types:
	- opened
	- edited
	- reopened
	- synchronize
	jobs:
	check-commit-message:
	name: Check Commit Message
	runs-on: ubuntu-latest
	steps:
	- name: Check commit subject complies with https://github.com/fluent/fluent-bit/blob/master/CONTRIBUTING.md#commit-changes
	uses: gsactions/commit-message-checker@v2
	with:
	pattern: '^[a-z0-9A-Z\-_\s\,\.\/]+\:[ ]{0,1}[a-zA-Z]+[a-zA-Z0-9 \-\.\:_\#=\/''\"\,><\+\[\]\!\*\\]+$'
	error: 'Invalid commit subject. Please refer to: https://github.com/fluent/fluent-bit/blob/master/CONTRIBUTING.md#commit-changes'
	checkAllCommitMessages: 'false'
	excludeDescription: 'true'
	accessToken: ${{ secrets.GITHUB_TOKEN }}

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