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

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https://hg.mozilla.org/integration/gaia-central/rev/57ca61c5a07e
Author: chirarobert <robert.chira@softvision.ro>
Desc: Merge pull request #25583 from viorelaioia/bug-1087383

Bug 1087383 - Add a test that sets the wallpaper from Gallery, by long p...

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https://hg.mozilla.org/integration/gaia-central/rev/84eebc0ac8ed
Author: Viorela Ioia <viorelaioia@gmail.com>
Desc: Bug 1087383 - Add a test that sets the wallpaper from Gallery, by long press on the screen
Bumping manifests a=b2g-bump