### What?
Previously, the create-payload-app install would properly update the env
vars in the new created `.env` file but kept outdated env vars in the
`.env.example` file.
I.e
If selecting a `postgres` DB for the blank or website template:
`.env` --> `DATABASE_URI` -->
`postgres://postgres:<password>@127.0.0.1:5432/test-cpa`
`.env.example` --> `DATABASE_URI` -->
`mongodb://127.0.0.1/payload-template-blank-3-0`
### Now
`.env` --> `DATABASE_URI` -->
`postgres://postgres:<password>@127.0.0.1:5432/test-cpa`
`.env.example` --> `DATABASE_URI` -->
`postgres://postgres:<password>@127.0.0.1:5432/test-cpa`