Don't run sql precheck if projects.get call fails

[modular-magician]

Fixes hashicorp/terraform-provider-google#7595

Reproduced locally, and this fixes the error the user experienced. This requires a whole bunch of host project / service project IAM setup that doesn't make it worth setting up an integration test for imo.

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Release Note Template for Downstream PRs (will be copied)

sql: fixed a case in `google_sql_database_instance` where we inadvertently required the `projects.get` permission for a service networking precheck introduced in `v3.44.0`

Derived from GoogleCloudPlatform/magic-modules#4141