refactor: remove net.Error.Temporary usage from domain cache

What does this MR do?

net.Error.Temporary is deprecated and Temporary errors are not well-defined. This method should not be used.

See https://github.com/golang/go/issues/45729
See https://tip.golang.org/doc/go1.18

TODO

• I added the Changelog trailer (e.g. Changelog: added) to the commits that need to be included in the changelog
• I added unit tests or they are not required
• I added acceptance tests or they are not required
• I added documentation (or it's not required)
• I followed code review guidelines
• I followed Go Style guidelines