[AWS::Lambda::Function] - [BUG] - VpcConfig.Ipv6AllowedForDualStack does not reset when removed from template

[disordered]

Name of the resource

AWS::Lambda::Function

Resource Name

No response

Issue Description

When Lambda is deployed into VPC with IPV6 support enabled and then updated to remove it from VPC, an error is produced.

This can be worked around by first, manually unsetting the Ipv6AllowedForDualStack flag in VPC configuration, either in UI console or CLI and then running the deployment with updated template.

Expected Behavior

Lambda should deploy without error and manual intervention.

Observed Behavior

Error message:

Resource handler returned message: "Ipv6AllowedForDualStack cannot be true without subnet or security groups. Please remove Ipv6AllowedForDualStack value from your request and try again.

Test Cases

Deploy VPC with IPV6 subnets and a Lambda function using that vpc, VpcConfig with Ipv6AllowedForDualStack set to true (you will have to set subnet and security group as well).
Change the template to disassociate Lambda from the VPC and remove the VpcConfig section.

Lambda should redeploy without errors.

Other Details

No response