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

========

https://hg.mozilla.org/integration/gaia-central/rev/681d1570992d
Author: autolander <kgrandon@mozilla.com>
Desc: Bug 1095469 - merge pull request #25960 from KevinGrandon:bug_1095469_collection_cdn_url to mozilla-b2g:master

========

https://hg.mozilla.org/integration/gaia-central/rev/3fdb28e9b5ea
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1095469 - [Collection] Use mozSettings for cdn url r=daleharvey r=rickychien
Bumping manifests a=b2g-bump