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

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https://hg.mozilla.org/integration/gaia-2_0/rev/7e6850d24179
Author: George <georgeiscoming@gmail.com>
Desc: Merge pull request #21881 from cctuan/1035453-v2.0

Bug 1035453 - [B2G][Camera] Pressing home does not function in the lockscreen camera with passcode lock enabled

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https://hg.mozilla.org/integration/gaia-2_0/rev/1c3405c4f540
Author: cctuan <georgeiscoming@gmail.com>
Desc: Bug 1035453 - [B2G][Camera] Pressing home does not function in the lockscreen camera with passcode lock enabled
Bumping manifests a=b2g-bump