This replaces all `nx` commands with `turbo` commands and removes Nx from the repository. All of the `project.json` files have been removed and any commands that broke with Turborepo have been adjusted.
* Removed Jetpack Changelogger from test js packages as they follow another approach for handling changelogs.
* Removed composer.json from api-core-tests, e2e-core-tests, e2e-environmnet and e2e-utils as they are no longer needed.
* Removed postinstall script from api-core-tests, e2e-core-tests, e2e-environment and e2e-utils packages, since they will no longer have a composer.json file.