Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_4/rev/ca576eaba856
Author: Rudy Lu <me@rudy.lu>
Desc: Merge pull request #17571 from RudyLu/keyboard/Bug983012_master

Bug 983012 - [Sora][Message][Input method]The virtual keyboard is
r=timdream(cherry picked from commit 77dab58bc492c26441132ee7641cfcda26f3ca90)
a=v1.3+, fabrice
Bumping manifests a=b2g-bump