Bumping gaia.json for 1 gaia-1_3 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_3/rev/38039733317e
Author: Dominic Kuo <dkuo@mozilla.com>
Desc: Merge pull request #16039 from dominickuo/bug-946556-new

Bug 946556 - [Music] Disable the play controls when using a bluetooth headset in a call, r=jimporter(cherry picked from commit 0ed0da7ea8c31e6df902deadaef4012f12911c39)

Conflicts:

	apps/music/index.html