Bumping gaia.json for 2 gaia-1_3 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_3/rev/0916d2473a61
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #15793 from alivedise/bugzilla/956938_v1.3/active-activity

Bug 956938 - Fix active activity reference

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https://hg.mozilla.org/integration/gaia-1_3/rev/51ef64cc74fd
Author: Alive Kuo <alegnadise@gmail.com>
Desc: Bug 956938 - Fix active activity reference
and remove the activity window correctly when there is multiple inline activities