github: switch issue templates to new labels

[mspncp]

(To be sure about the syntax, I created a test template using the wizard.)

[mspncp]

Merged to cfa71c5 and removed the [feature] and the [bug] label.

[mattcaswell]

I notice that you removed the "approval: done" label when you added "ready to merge"...is that they way we should do things - or should we keep the "approval: done" after "ready to merge" is additionally added? To me it makes more sense to keep it.

[mspncp]

I wasn’t sure myself whether I should remove it or not. If you prefer to keep it, I‘m ok with it.

[mattcaswell]

To me the "approval: done" status is not something that is lost simply because we have additionally gained the "ready to merge" status.

[mspncp]

Ok, then I'll restore the label on the recent tickets.

(FWIW: bulk adding/removal of labels is possible using multiselection on the issue search page.)

[mspncp]

To me the "approval: done" status is not something that is lost simply because we have additionally gained the "ready to merge" status.

P.S: The motivation behind removing the 'approval: done' label was to consider 'approval: *' and 'ready for merge' as mutual exclusive ticket states. But viewing them as independent properties makes equally sense.

Anyway, I think the @openssl/omc needs to state a clear policy for handling the 'approval: *' and 'ready to merge' labels, in particular in the case when the 'approval: ready' state needs to be withdrawn (e.g. because there was a force push after 'ready to merge'). Partial support by a GitHub bot might be helpful, but not sufficient for all use cases.