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

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https://hg.mozilla.org/integration/gaia-central/rev/65263e2002e3
Author: Luke Chang <lchang@mozilla.com>
Desc: Merge pull request #12285 from luke-chang/913397_keyboard_1.5x_graphics

Bug 913397 - [Keyboard] Make keyboard app support 1.5x graphics, r=rudylu

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https://hg.mozilla.org/integration/gaia-central/rev/53f460a7135e
Author: Luke Chang <lchang@mozilla.com>
Desc: Bug 913397 - [Keyboard] Make keyboard app support 1.5x graphics