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

========

https://hg.mozilla.org/integration/gaia-2_1/rev/6a6a3d120483
Author: Ryan VanderMeulen <ryanvm@gmail.com>
Desc: Merge pull request #24380 from anefzaoui/bug-1062964

[v2.1] Bug 1062964 - RTL in Notifications toaster is broken

========

https://hg.mozilla.org/integration/gaia-2_1/rev/2d810316d170
Author: Ahmed Nefzaoui <nefzaoui.ahmed@hotmail.com>
Desc: Bug 1062964 - RTL in Notifications toaster is broken
Bumping manifests a=b2g-bump