Added a note that failover_target is not supported for Postgres Database.

[ibhaskar2]

Failover_target is not supported for Postgres Database.
b/290620351

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Release Note Template for Downstream PRs (will be copied)

[modular-magician]

Hello! I am a robot. It looks like you are a community contributor. @hao-nan-li, a repository maintainer, has been assigned to review your changes. If you have not received review feedback within 2 business days, please leave a comment on this PR asking them to take a look.

You can help make sure that review is quick by doing a self-review and by running impacted tests locally.

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

Terraform GA: Diff ( 2 files changed, 2 insertions(+), 1 deletion(-))
Terraform Beta: Diff ( 2 files changed, 2 insertions(+), 1 deletion(-))
TF Conversion: Diff ( 2 files changed, 3 insertions(+), 3 deletions(-))

[modular-magician]

Tests analytics

Total tests: 2871
Passed tests 2570
Skipped tests: 299
Affected tests: 2

Action taken

Found 2 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccContainerAwsNodePool_BetaBasicHandWritten|TestAccComputeFirewallPolicyRule_multipleRules

Get to know how VCR tests work

[modular-magician]

$\textcolor{red}{\textsf{Tests failed during RECORDING mode:}}$
TestAccContainerAwsNodePool_BetaBasicHandWritten[Error message] [Debug log]
TestAccComputeFirewallPolicyRule_multipleRules[Error message] [Debug log]

$\textcolor{red}{\textsf{Please fix these to complete your PR.}}$
View the build log or the debug log for each test

[aleksandersumowski]

Hi Ishant @ibhaskar2, any particular reason why Postgresql is not supported? Cloud SQL Postgresql itself does support ADR and assigning designated failover target

https://cloud.google.com/sql/docs/postgres/use-advanced-disaster-recovery