github.com/pkg/errors should be replaced by stdlib "errors"

[mjtrangoni]

Hi,

Checking my openziti_exporter project with the latest golangci-lint depguard plugin, it turns out that ziti is still using the already deprecated github.com/pkg/errors package.

See,

grep -Er 'github.com/pkg/errors' * | wc -l
     249

If you agree, I can open some "small" PRs replacing it with stdlib errors. Some other projects like prometheus started already the same procedure.

[plorenz]

I've got mixed feelings about this. Even though pkg/errors is an archived project, it's a very simple project and I don't anticipate that issues will crop up. stdlib errors doesn't support stacks, which can be quite useful. I also like the Wrap syntax better than the fmt with %w, as it standardizes the format.

On the flip side, no one can report issues to an archived project, so if there is an issue, we may never find out about it. Also we haven't used the stack support in some time, so maybe we don't need it.

@ekoby suggested that we remove it from all the supporting libraries, at least, so it doesn't cause issues for developers using the SDK, which I think is reasonable. Then we can think about removing it from ziti.