pulls external providers for TestAccCGCSnippet_sqlDatabaseInstanceSql…

[modular-magician]

…serverExample

Fixes hashicorp/terraform-provider-google#11825

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Release Note Template for Downstream PRs (will be copied)

sql: updated `google_sql_user.sql_server_user_details` to be read only. Any configuration attempting to set this field is invalid and will cause the provider to crash during plan time.

Derived from GoogleCloudPlatform/magic-modules#6165