fix the random order of block_device_mappings render

[AldoFusterTurpin]

What this PR does

Includes a new function to get the keys of the map used for block_device_mappings to access elements in deterministic order to avoid false changes in terraform diff.

Why we need it ?

When we render the terraform in kops, sometimes we get a diff like this

stating that there are changes in the block_device_mappings, but the only thing that changes is the order of those devices, and this happens randomly because we use a map to store those here, here and here.

The solution

Simply sort the keys of the map and always access the maps using a deterministic order to avoid getting false changes shown in the terraform diff.

Additional notes

I have used generics for simplicity and included a unit test for the new function.

The only thing that changes is that now we do not iterate the maps directly using a "for" construct but instead iterate over the keys of the map in order and access the values of the maps using the keys. This change does not affect the behavior, just ensures that we always iterate over the devices in the same order.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: AldoFusterTurpin / name: Aldo Fuster Turpin (ba0a94f)

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[k8s-ci-robot]

Hi @AldoFusterTurpin. Thanks for your PR.

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[hakman]

/ok-to-test

[AldoFusterTurpin]

/retest

[hakman]

Thanks for the PR @AldoFusterTurpin. There are a few nits that should be addressed before merging the PR.

[AldoFusterTurpin]

Thanks for the PR @AldoFusterTurpin. There are a few nits that should be addressed before merging the PR.

Thanks for the review! Checking now. 👌

[hakman]

Thanks @AldoFusterTurpin!
/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: rifelpet

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