Use modern Go constructs

[HadrienPatte]

• Have you signed the CLA?

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Use modern Go constructs:

• replace interface{} with any (available since go1.18)
• replace 3-clause loop with range loop (available since go1.22)
• use slices package (available since go1.21)

[github-actions]

Command	Mean [s]	Min [s]	Max [s]	Relative
BASE	8.504 ± 0.021	8.477	8.546	1.00
HEAD	8.509 ± 0.020	8.469	8.543	1.00 ± 0.00

[letFunny]

@HadrienPatte Thanks for this and apologies for not reviewing it. At the moment we are focused on delivering some major features that will significantly improve the UX. Once we are done with those we will prioritize reviewing and merging this PR.

[reneleonhardt]

Seems odd, upgrading go to 1.23 in the meantime without merging all those nice modernizations first...

[HadrienPatte]

@canonical/rocks gentle bump on this PR ;)

[letFunny]

Thanks for this PR and apologies for taking long to review. Even though it looks simple, every change to slices.Delete and slices.Clone has to be inspected manually because they have slightly different semantics than the code that was written before them (i.e. they now respect nilness).

While this is approved, it will still remain low priority so it might get picked up in the next couple of weeks. Thanks again for contributing!

[letFunny]

@HadrienPatte can you push an empty commit git commit --allow-empty ... to trigger the CI, there seems to be a bug in Github.

[niemeyer]

Thanks for these!