Create porting issues automatically using GitHub action

[Enkidu93]

We should create a GitHub action to automatically open a 'port such-and-such' issue in machine.py when a PR goes through in Machine and vice-versa. It's a lot to keep track of and there have been a handful of times that I've realized that a long-ago commit to one repo was never ported to the other (and there probably still are discrepancies like this out there). Even if some of the issues created are unnecessary since porting is not always needed, we can at least keep track of that fact somewhere linked to the PR.