fix NPE on client disconnect to clear client session stats #204

	#
	# Copyright © 2016-2024 The Thingsboard Authors
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.
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	name: License header format

	on:
	push:
	branches:
	- 'main'
	- 'develop/*'

	jobs:
	license-format:
	runs-on: ubuntu-latest

	steps:
	- name: Checkout Repository
	uses: actions/checkout@v4

	- name: Set up JDK
	uses: actions/setup-java@v4
	with:
	distribution: 'corretto' # https://github.com/actions/setup-java?tab=readme-ov-file#supported-distributions
	java-version: '21'
	cache: 'maven' # https://github.com/actions/setup-java?tab=readme-ov-file#caching-sbt-dependencies

	- name: License header format
	run: mvn -T 1C license:format

	- name: License header format (msa/black-box-tests/)
	run: mvn -T 1C license:format -f msa/black-box-tests/

	- name: Set Git user information
	run: \|
	git config user.name "ThingsBoard Bot"
	git config user.email "noreply@thingsboard.io"
	- name: Check and push changes
	run: \|
	git diff --exit-code \|\| git commit -am "License header format" && git push

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