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

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https://hg.mozilla.org/integration/gaia-central/rev/50b087245392
Author: Amir Nissim <amirnissim@gmail.com>
Desc: Merge pull request #12534 from EverythingMe/911767-cloudapps-editmode

Bug 911767 - [e.me][bug] Long press on pinned cloud apps doesn't toggle ...

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https://hg.mozilla.org/integration/gaia-central/rev/0ce631e5c8db
Author: Amir Nissim <amirn@everything.me>
Desc: Bug 911767 - [e.me][bug] Long press on pinned cloud apps doesn't toggle edit mode [r=crdlc]