docs: update `ddev get` to `ddev add-on get` in readme #646

	name: tests
	on:
	pull_request:
	push:
	branches: [ main ]

	schedule:
	- cron: '25 08 * * *'

	workflow_dispatch:
	inputs:
	debug_enabled:
	type: boolean
	description: Debug with tmate
	required: false
	default: false

	# Required permissions for keep-alive, used by ddev/github-action-add-on-test
	permissions:
	actions: write

	defaults:
	run:
	shell: bash

	jobs:
	tests:
	defaults:
	run:
	shell: bash

	strategy:
	matrix:
	ddev_version: [stable, HEAD]
	fail-fast: false

	# We need to use the ubuntu-20.04 image because the sqlsrv service uses the
	# mcr.microsoft.com/mssql/server:2019-CU12-ubuntu-20.04 image.
	# See the issue https://github.com/ddev/ddev-sqlsrv/issues/29 for more
	# details.
	runs-on: ubuntu-20.04

	steps:
	- uses: ddev/github-action-add-on-test@v2
	with:
	ddev_version: ${{ matrix.ddev_version }}
	token: ${{ secrets.GITHUB_TOKEN }}
	debug_enabled: ${{ github.event.inputs.debug_enabled }}
	addon_repository: ${{ env.GITHUB_REPOSITORY }}
	addon_ref: ${{ env.GITHUB_REF }}

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