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

========

https://hg.mozilla.org/integration/gaia-central/rev/7c807b9e73ea
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #16171 from bebef1987/ftu_wifi

Bug 970828 - test_ftu_skip_tour often failing to connect to WiFi

========

https://hg.mozilla.org/integration/gaia-central/rev/fe054f31d9a8
Author: Bebe <bebe@mozilla.ro>
Desc: Bug 970828 - test_ftu_skip_tour often failing to connect to WiFi
Bumping manifests a=b2g-bump