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/11f2d62d29f7
Author: Rex KM Lee <rexboy@mozilla.com>
Desc: Merge pull request #15594 from rexboy7/fix-bug959660-v1.3

Bug 959660 - [System] Prevent show/hide attention screen again when it's...

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https://hg.mozilla.org/integration/gaia-1_3/rev/dea0358805d9
Author: Rex Lee <rexboy@mozilla.com>
Desc: Bug 959660 - [System] Prevent show/hide attention screen again when it's already hiding