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

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https://hg.mozilla.org/integration/gaia-central/rev/b873d75cdc72
Author: Evyatar Amitay <evyatron@gmail.com>
Desc: Merge pull request #12549 from EverythingMe/results-design

[Bug 910324] unify icon sizes across the board [r=crdlc]

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https://hg.mozilla.org/integration/gaia-central/rev/bc1b26fe35e7
Author: Evyatar Amitay <evyatron@gmail.com>
Desc: [Bug 910324] unify icon sizes across the board [r=crdlc]