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

========

https://hg.mozilla.org/integration/gaia-central/rev/9b0f4215a31b
Author: Diego Marcos <diego.marcos@gmail.com>
Desc: Merge pull request #21509 from dmarcos/bug1035383

Bug 1035383 - [B2G][Camera] The user is able to use the camera when batt...

========

https://hg.mozilla.org/integration/gaia-central/rev/a2171750ec89
Author: Diego Marcos <diego.marcos@gmail.com>
Desc: Bug 1035383 - [B2G][Camera] The user is able to use the camera when battery is below 5%
Bumping manifests a=b2g-bump