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

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https://hg.mozilla.org/integration/gaia-central/rev/1980e95de84b
Author: Amir Nissim <amirnissim@gmail.com>
Desc: Merge pull request #20564 from EverythingMe/1025844-stored-bg

Bug 1025844 - [Collections] Missing Default Icon and faster Background load

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https://hg.mozilla.org/integration/gaia-central/rev/b88060078127
Author: Amir Nissim <amirnissim@gmail.com>
Desc: Bug 1025844 - [Collections] Missing Default Icon and faster Background load
Bumping manifests a=b2g-bump