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/0489518433b0
Author: Dominic Kuo <dkuo@mozilla.com>
Desc: Merge pull request #15653 from dominickuo/bug-946556

Bug 946556 - [Music] Disable the play controls when using a bluetooth headset in a call, r=jimporter(cherry picked from commit 0646bf911164ca9e2f80a6b703558bed35b449b2)

Conflicts:

	apps/music/index.html