Update Readme to set tags as optional

[avh01]

TL;DR

Readme states incorrectly that tags are required, this is wrong they should be marked as optional

Expected behavior

Update Readme

Observed behavior

Incorrect information in Readme related to tags being required

Terraform Configuration

N/A

Terraform Version

v1.10.5

Terraform Provider Versions

registry.terraform.io/hashicorp/google v6.50.0

Additional information

No response

[avh01]

I submitted a merge to correct the documentation ommission.