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

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https://hg.mozilla.org/integration/gaia-central/rev/329b001bc2e0
Author: Ran Ben Aharon <ran@everything.me>
Desc: Merge pull request #12637 from EverythingMe/905455-oversized-icons

[Bug 905455] Fix HDPI issues [r=crdlc]

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https://hg.mozilla.org/integration/gaia-central/rev/a8a41825321b
Author: Evyatar Amitay <evyatron@gmail.com>
Desc: [Bug 905455] Fix HDPI issues [r=crdlc]