Bumping gaia.json for 2 gaia-central revision(s) a=gaia-bump

========

https://hg.mozilla.org/integration/gaia-central/rev/8c8d0a8bc239
Author: George <georgeiscoming@gmail.com>
Desc: Merge pull request #14941 from cctuan/953007

Bug 953007 - [Gaia] [Build] Error when make install-gaia APP=uitest

========

https://hg.mozilla.org/integration/gaia-central/rev/eb791416f8cd
Author: cctuan <georgeiscoming@gmail.com>
Desc: Bug 953007 - [Gaia] [Build] Error when make install-gaia APP=uitest