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

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https://hg.mozilla.org/integration/gaia-central/rev/0d2075c3e9ed
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Merge pull request #11160 from timdream/fix-icon-selection-dppx

Bug 883819 - Use 90@1x icon as 60@1.5x icon for now, r=crdlc

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https://hg.mozilla.org/integration/gaia-central/rev/3f94f5fc1600
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Bug 883819 - Use 90@1x icon as 60@1.5x icon for now