feat: (IAC-878) support external cds postgres

[dhoucgitter]

Changes

Along with the Crunchy 5 changes made in 2022.10, a blanket support statement was made that CDS Postgres should be internal only. Other teams now want to use CDS externally so allow DAC to configure and deployments to use external default and cds-postgres PostgreSQL instances for 2022.12 cadence and later.

• Change message boundary to pre 2022.12 cadences for cds-postgres instance must be internal only
• Generate user.env, secrets generator and dataserver-transformer for an external cds-postgres instance
• Modify dataserver-transformer template so that it can generate sas-platform-postgres-dataserver-transformer and sas-cds-postgres-dataserver-transformer outputs with expected dataserver names
• Include cds-postgres overlay for an external cds-postgres instance
• Use SharedServices as default cds-postgres database name when no setting is provided

Tests

See internal ticket for additional details.

Scenario	Task	Provider	K8s	V4_DEPLOYMENT_OPERATOR_ENABLED	Deployment Method	Viya TLS	Cadence	Notes
2	External cds-postgres pre 2022.12	Azure	v1.23.14	false	Ansible	full-stack	2022.11	As expected DAC displays the following message and exits: "CDS postgres instance must be internal server. To use CDS postgres, please reconfigure your infrastructure to set all your postgres servers internal"
3	External cds-postgres 2022.12	Azure	v1.23.14	false	Ansible	full-stack	2022.12	As expected deployment is allowed, both default-dataserver-transformer, cds-postgres-dataserver-transformer are generated with expected content.
4	fast:2020 VA-VDMML default & cds-postgres external	AWS	1.23.14	false	Ansible	full-stack	fast:2020	Deployment stabilized with all pods Running, configured the same custom db name in ansible-vars for each PG server
5	risk-cirrus, TLS disabled	AWS	1.23.14	false	Ansible	disabled	stable:2023.01	All sas-risk-cirrus pods stabilized and running. Verified sas-risk-data pod successful connection to external cds-postgres instance and SCHEMA creation.
7	risk-cirrus, TLS enabled	AWS	1.23.14	false	Ansible	front-door	stable:2023.01	Deployment stabilized, all sas-risk-cirrus-pods running. sas-risk-data pod log shows successful connection to ssl_enabled external cds-postgres instance and SCHEMA creation.
8	risk-cirrus, TLS enabled	Azure	1.24.6	false	Ansible	front-door	stable:2023.01	sas-risk-data pod log shows successful connection to external cds-postgres instance and SCHEMA creation. Deployment stabilized with all risk-cirrus pods Running.
9	risk-cirrus, Deployment Operator, TLS enabled	Azure	1.24.6	true	Ansible	front-door	stable:2023.01	DO enabled. Deployment stabilized, all sas-risk-cirrus-pods Running. sas-risk-data pod log showing successful connection to ssl_enabled external cds-postgres instance and SCHEMA creation.

[dhoucgitter]

@thpang, task name updated, ready for final review.