doc(redis): auth_string optional parameter does not exist

[Pinimo]

Part of hashicorp/terraform-provider-google#9958
Fixes hashicorp/terraform-provider-google#12563

redis: Remove `auth_string` parameter from doc as it is only an output

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[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 ( 1 file changed, 1 deletion(-))
Terraform Beta: Diff ( 1 file changed, 1 deletion(-))
TF Validator: Diff ( 2 files changed, 3 insertions(+), 3 deletions(-))

[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 ( 1 file changed, 1 deletion(-))
Terraform Beta: Diff ( 1 file changed, 1 deletion(-))
TF Validator: Diff ( 2 files changed, 3 insertions(+), 3 deletions(-))

[Pinimo]

Although I was able to build the providers, I would prefer not to run tests, because I don't want to run them on any corporate GCP project, and my edit is only about documentation. I hope this makes sense 🙂

[zli82016]

Although I was able to build the providers, I would prefer not to run tests, because I don't want to run them on any corporate GCP project, and my edit is only about documentation. I hope this makes sense 🙂

It makes sense, as it is only documentation change.

[zli82016]

LGTM