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

========

https://hg.mozilla.org/integration/gaia-central/rev/a76d2ef6040e
Author: Florin Strugariu <bebef_1987@yahoo.com>
Desc: Merge pull request #13293 from stupchiy/issue_931865

Bug 931865 - gaia test is_app_installed doesn't check the last page of apps

========

https://hg.mozilla.org/integration/gaia-central/rev/ca5b90284164
Author: Sergey Tupchiy <sergey.tupchiy@optile.de>
Desc: changed logic of is_app_installed, Bug #931865