Do what you need to do to finish your PhD and get out.
You don't have to tell anyone about your plans to leave academia, including your supervisor.
Now that your are in your last year, plan your last months well. Do your week by week plan on what you need to do until you submit. Write down your essential tasks and commit to it with everything you have.
You owe it to yourself to work hard and finish the damn PhD since you are so close. Then get out with your PhD award in your hands and do something else that you love outside of academia.
There is no security in a research life in the university, living from grant to grant, and the pay is very low. Your decision to go is wise, but do not tell anyone until you leave academia.You do not want to be sabotaged (eg your superviosr takes you off first author because "you don't need it anymore", or your team treats you poorly because they won't be collaborating with you in the future)