Update references from "MARKETPLACE PROJECT ID" to "PROVIDER ID"

[apgiorgi]

The Marketplace provider ID can be different from the project ID. So we need to change all documentation references (and variable names) from "marketplace project id" in the .toml file to "provider id". This property should be retrieved from the procurement portal

This property should be renamed:

doit-easily-marketplace/docs/terraform/app_deploy/custom-settings.toml

Line 2 in 7b0eb8b

marketplace_project = '@none None' # This should be set to the name of the project you want to use, otherwise an error will be thrown.