IPv6 external IP support

[mohag]

TL;DR

access_config can be configured, ipv6_access_config can't, so static IPv6 IPs can't be configured on the bastion host

Terraform Resources

https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance#nested_ipv6_access_config

Detailed design

Add an ipv6_access_config variable that is passed similar to access_config is passed currently. (It might be necessary to add a flag similar to `external_ip` to toggle the creation of an IPv6 IP. `enable_ipv6` is my suggestion. (it might be an internal / external IP, depending on the VPC's configuration)

Additional information

No response

[github-actions]

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[github-actions]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days

[github-actions]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days

[mohag]

.

[github-actions]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days

[mohag]

Apparently one needs to encourage +1 comments here to keep the bot at bay....