Bumping gaia.json for 3 gaia-central revision(s) a=gaia-bump

========

https://hg.mozilla.org/integration/gaia-central/rev/25802a660979
Author: Lyall Jonathan Di Trapani <lj.ditrapani@gmail.com>
Desc: Bug 935319 - Improve gaia-ui-tests documentation for users getting starting with b2g-desktop builds. r=dhunt

========

https://hg.mozilla.org/integration/gaia-central/rev/692decf70683
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #13863 from askeing/940883

Bug 940883 - Fix test_everythingme_add_collection.py

========

https://hg.mozilla.org/integration/gaia-central/rev/a0605b01d60a
Author: askeing <askeing@gmail.com>
Desc: Bug 940883 - Fix test_everythingme_add_collection.py