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

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https://hg.mozilla.org/integration/gaia-central/rev/5102fe0a87af
Author: Rudy Lu <me@rudy.lu>
Desc: Merge pull request #15637 from anefzaoui/keyboard-outline-chars-ar

 Bug 897362 - [InputMethod][Arabic]The characters overflow the keyboard when set the keyboard layouts as the Arabic.
r=rudylu

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https://hg.mozilla.org/integration/gaia-central/rev/5f38da4f3133
Author: Ahmed Nefzaoui <nefzaoui.ahmed@hotmail.com>
Desc: The characters overflow the keyboard when set the keyboard layouts as the Arabic.
Bumping manifests a=b2g-bump