Upgrade crossguard content to aws.s3.BucketV2

[t0yv0]

Policy packs written against aws.s3.Bucket do not translate to aws.s3.BucketV2 setups in a straightforward way, especially when deprecated attributes like "acl" are taken into account. The affected content lives here:

content/docs/iac/packages-and-automation/crossguard

Separating this out into a dedicated ticket as there is a bit of work involved here.

References

• https://github.com/orgs/pulumi/projects/180
• https://github.com/pulumi/home/issues/3633