chore(asg): update to 8.x

[adamconnelly]

Description of the change

This PR is actually a follow-up from this PR by @jeohist: #102.

The problem is that the AWS version that our examples are pinned to isn't compatible with the latest version of the module. I've just gone ahead and added another commit on top of @jeohist's change to fix that since it's tricky for external contributors to run the test cases.

Type of change

• Bug fix (non-breaking change that fixes an issue);
• New feature (non-breaking change that adds functionality);
• Breaking change (fix or feature that would cause existing functionality to not work as expected);
• Documentation (a documentation or example fix not affecting the infrastructure managed by this module);

Checklists

Development

• All necessary variables have been defined, with defaults if applicable;
• The code is formatted properly;

Code review

• The module version is bumped accordingly;
• Spacelift tests are passing;
• This pull request has a descriptive title and information useful to a reviewer. There may be a screenshot or screencast attached;
• This pull request is no longer marked as "draft";
• Reviewers have been assigned;
• Changes have been reviewed by at least one other engineer;