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

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https://hg.mozilla.org/integration/gaia-central/rev/687919bdd494
Author: Luke Chang <lchang@mozilla.com>
Desc: Merge pull request #13681 from luke-chang/933252_fix_keyboard_jskanji

Bug 933252 - jp-kanji keyboard doesn't work, r=rudylu

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https://hg.mozilla.org/integration/gaia-central/rev/62e9b4f1e78d
Author: Luke Chang <lchang@mozilla.com>
Desc: Bug 933252 - jp-kanji keyboard doesn't work