AWS system test eks and fargate profile: get subnets as external parameter

[vincbeck]

In both system tests example_eks_with_fargate_profile and example_eks_with_fargate_in_one_step subnets are created within the system test. In order to create these subnets, an available CIDR block is created with the function _get_next_available_cidr. When both tests are running at the same time, some race condition can happen and both tests might pick the same CIDR blocks which then result as a failure.

To avoid that, I rather create these subnets outside of the system test and fetch them as external parameter

[vandonr-amz]

nice, with a side benefit of making the test simpler to read, and also faster as deleting the nat gateway was taking ~45s :D

[o-nikolas]

Agreed, great change. So beautiful when you can just use the variable fetcher to hide the nasty bits of creating/managing resources 😄

[ferruzzi]

I do love a negative linecount.

For posterity: generally we would prefer to set up and tear down in the test, this is only getting changed because of the race condition it was causing.

[o-nikolas]

For posterity: generally we would prefer to set up and tear down in the test, this is only getting changed because of the race condition it was causing.

Good call out 👍

[o-nikolas]

FYI: @vincbeck is just making some internal preparations (to create the subnets that this test now expects to be present). I'll merge these changes tomorrow when that is done.