Enforce copyright notices at pre-commit or CI level

[jgsogo]

From #63 (comment)

Every source file needs to have a copyright notice in the first lines. When changing a file, we have to update this copyright notice with the year it was last modified. Of course it can happen at most once every year for each file.... however many contributors (and reviewers) might forget about it.

Is there anything we can do as a pre-commit hook or CI level to check that these notes are updated?

cc/ @taalexander

[mtreinish]

You can adapt this script and run it as part of a ci job https://github.com/Qiskit/qiskit-terra/blob/main/tools/verify_headers.py that will error if a source file is missing the appropriate header