refactor: fix the testing src-layout structure and use relative imports #2039

	name: Data Charm Tests

	on:
	push:
	branches:
	- main
	pull_request:
	workflow_call:

	jobs:
	db-charm-tests:
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	include:
	- charm-repo: canonical/postgresql-operator
	commit: 7219d1ed1a118abbfca23aeacf3b7bf67e81a937 # rev480 rev479 2024-09-23T16:12:27Z
	- charm-repo: canonical/postgresql-k8s-operator
	commit: 5c2ae046546a7d163b9d040d6a12d1abc0ca1f70 # rev398 rev397 2024-09-24T19:23:37Z
	- charm-repo: canonical/mysql-operator
	commit: 9fe60aa9f0a00636e06902d0849d36e1e1525df2 # 2024-09-22
	- charm-repo: canonical/mysql-k8s-operator
	commit: 61db833ba8318773de565d7d9b56031baf3e75f7 # 2024-09-19T11:48:20Z
	steps:
	- name: Checkout the ${{ matrix.charm-repo }} repository
	uses: actions/checkout@v4
	with:
	repository: ${{ matrix.charm-repo }}
	ref: ${{ matrix.commit }}

	- name: Checkout the operator repository
	uses: actions/checkout@v4
	with:
	path: myops

	- name: Install patch dependencies
	run: pip install poetry~=1.6

	- name: Update 'ops' dependency in test charm to latest
	run: \|
	if [ -e "requirements.txt" ]; then
	sed -i -e "/^ops[ ><=]/d" -e "/canonical\/operator/d" -e "/#egg=ops/d" requirements.txt
	echo -e "\ngit+$GITHUB_SERVER_URL/$GITHUB_REPOSITORY@$GITHUB_SHA#egg=ops" >> requirements.txt
	else
	sed -i -e "s/^ops[ ><=].*/ops = {path = \"myops\"}/" pyproject.toml
	poetry lock --no-update
	fi

	- name: Install dependencies
	run: pip install tox~=4.2

	- name: Run the charm's unit tests
	run: tox -vve unit

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