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

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https://hg.mozilla.org/integration/gaia-central/rev/857c2c4405de
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #18624 from alison-shiue/bug-999965

Bug 999965 - enable DSDS tests via manifest with the Flame device name

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https://hg.mozilla.org/integration/gaia-central/rev/0facc68ca11b
Author: alison-shiue <alison@alison-u-pc.(none)>
Desc: Bug 999965 - enable DSDS tests via manifest with the Flame device name
Bumping manifests a=b2g-bump