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

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https://hg.mozilla.org/integration/gaia-central/rev/faa3e80891f9
Author: AndreiH <andrei.hutusoru@softvision.ro>
Desc: Merge pull request #21583 from mozilla-b2g/revert-21432-bug_924835

Revert "Bug 924835 - Create a test for receiving a call with a locked sc...

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https://hg.mozilla.org/integration/gaia-central/rev/1c8b88472aaa
Author: Florin Strugariu <bebef_1987@yahoo.com>
Desc: Revert "Bug 924835 - Create a test for receiving a call with a locked screen"
Bumping manifests a=b2g-bump