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

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https://hg.mozilla.org/integration/gaia-central/rev/33c03a1044f7
Author: steveck-chung <schung@mozilla.com>
Desc: Merge pull request #12512 from evhan55/903960

Bug 903960 - [SMS] Switching to message view when selecting left side of the message. r=steveck-chung

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https://hg.mozilla.org/integration/gaia-central/rev/a6ba0a9c8614
Author: Evelyn Eastmond <evhan55@gmail.com>
Desc: Bug 903960 - [SMS] Switching to message view when selecting left side of the message