feat: Add single_nat_gateway_subnet_index to choose NAT Gateway public subnet

[cosimomeli]

Description

Add single_nat_gateway_subnet_index to choose in which public subnet the single NAT Gateway must be created.

Motivation and Context

Currently, the single NAT Gateway is created in the first public subnet and, thus, in the first Availability Zone. This variable allows the user to choose which AZ the NAT Gateway will be created in.

Breaking Changes

This is fully backward compatible and does not introduce any breaking changes.

How Has This Been Tested?

• I have updated at least one of the examples/* to demonstrate and validate my change(s)
• I have tested and validated these changes using one or more of the provided examples/* projects

• I have executed pre-commit run -a on my pull request

[github-actions]

This PR has been automatically marked as stale because it has been open 30 days
with no activity. Remove stale label or comment or this PR will be closed in 10 days

[cosimomeli]

I'm still interested in this feature.

[github-actions]

This PR has been automatically marked as stale because it has been open 30 days
with no activity. Remove stale label or comment or this PR will be closed in 10 days

[cosimomeli]

I'm still waiting for Senpai to notice me.

[github-actions]

This PR has been automatically marked as stale because it has been open 30 days
with no activity. Remove stale label or comment or this PR will be closed in 10 days

[cosimomeli]

I'm still waiting for Senpai to notice me.

[github-actions]

This PR has been automatically marked as stale because it has been open 30 days
with no activity. Remove stale label or comment or this PR will be closed in 10 days

[cosimomeli]

I'm still waiting for Senpai to notice me.

[github-actions]

This PR has been automatically marked as stale because it has been open 30 days
with no activity. Remove stale label or comment or this PR will be closed in 10 days

[cosimomeli]

I'm still waiting for Senpai to notice me.

[github-actions]

This PR has been automatically marked as stale because it has been open 30 days
with no activity. Remove stale label or comment or this PR will be closed in 10 days

[cosimomeli]

I'm still waiting for Senpai to notice me.

[markusgulden]

This is a totally legit feature in my opinion.
Soft limit default for NAT gateways per AZ is 5, and at the moment, that is reached with 5 VPCs, so being able to choose the AZ actively would be handy.

[github-actions]

This PR has been automatically marked as stale because it has been open 30 days
with no activity. Remove stale label or comment or this PR will be closed in 10 days

[cosimomeli]

I'm still waiting for Senpai to notice me.

[github-actions]

This PR has been automatically marked as stale because it has been open 30 days
with no activity. Remove stale label or comment or this PR will be closed in 10 days

[cosimomeli]

I'm still waiting for Senpai to notice me.

[bryantbiggs]

noticed and we won't be accepting this change

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues. If you have found a problem that seems related to this change, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.