Deprecate google_firebase_project_location

[modular-magician]

Deprecate google_firebase_project_location. This resource was introduced before google_firebase_storage_bucket and google_firestore_database were available. The underlying API is being deprecated. The recommended way now is to use either or both of the above mentioned resources with an explicitly specified location.

If this PR is for Terraform, I acknowledge that I have:

• Generated Terraform providers, and ran make test and make lint in the generated providers to ensure it passes unit and linter tests.
• Ran relevant acceptance tests using my own Google Cloud project and credentials (If the acceptance tests do not yet pass or you are unable to run them, please let your reviewer know).
• Read Write release notes before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

firebase: deprecated `google_firebase_project_location` in favor of `google_firebase_storage_bucket` and `google_firestore_database`

Derived from GoogleCloudPlatform/magic-modules#8301