Add testing for AWS provider caches

[engedaam]

Description

What problem are you trying to solve?

Karpenter has had some caching bugs that have occurred in the past few months:

• consistent errors from CreateFleet API for 70 minutes preventing scale up completely  #5850
• insufficient capacity, all requested instance types were unavailable during launch #5578
• Karpenter memory utilisation balloons after upgrade to 0.32.2 #5196

We will need to add additional testing to validate the correct information is being added to our AWS provider caches. These provider will require additional testing:

• Instance Type Provider
• Subnet Provider
• Security Group Provider
• Launch Template Provider
• Instance Profile Provider

We will need to add some basic tests that will validate that the caches in these providers contain values we expect.

• Please vote on this issue by adding a 👍 reaction to the original issue to help the community and maintainers prioritize this request
• Please do not leave "+1" or "me too" comments, they generate extra noise for issue followers and do not help prioritize the request
• If you are interested in working on this issue or have submitted a pull request, please leave a comment

[engedaam]

Completed with these PRs:

• test: Add unit test to validate the instancetype cache #5917
• test: Add unit cache tests for LaunchTemplate #6006
• test: Add unit cache tests for security groups #5990
• test: Add unit cache tests for subnets #5978