[ironic] Moving Aija to core-emeritus

Hi all, As many of you may already know, Aija is no longer actively working on OpenStack. She informed many Ironic cores over email of this last week. I asked her if she expected to contribute on her own time and she said no. In order to ensure we keep core reviewer lists up to date, I suggest we move Aija to core-emeritus status, removing core permissions from gerrit. If she decides to begin working on OpenStack again in the future, we'd obviously quickly return core permissions. What do you think? -- Jay Faulkner Ironic PTL TC Member P.S. A huge thanks to Aija for her hard work on the sushy project and the Dell driver in Ironic.