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

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https://hg.mozilla.org/integration/gaia-central/rev/7d0200d2ebc4
Author: John Hu <johu@mozilla.com>
Desc: Merge pull request #12960 from huchengtw-moz/vide/Bug_923297_video_duration_mismatch

Bug 923297 - [B2G][Video] Video duration can appear off by a second when..., r=djf

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https://hg.mozilla.org/integration/gaia-central/rev/f1a9b2b2b56f
Author: John Hu <johu@mozilla.com>
Desc: Bug 923297 - [B2G][Video] Video duration can appear off by a second when played in Video app