.github: Add note how to find version before fwupd 0.9.6
.github: Add note how to find version before fwupd 0.9.6

Fixes: https://github.com/hughsie/fwupd/issues/300

fwupd/fwupd,hughsie/fwupd,vathpela/fwupd,hughsie/fwupd,hughsie/fwupd,vathpela/fwupd,superm1/fwupd,vathpela/fwupd,hughsie/fwupd,vathpela/fwupd,superm1/fwupd,fwupd/fwupd,fwupd/fwupd,fwupd/fwupd,superm1/fwupd