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

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https://hg.mozilla.org/integration/gaia-central/rev/8a322556bd47
Author: AndreiH <andrei.hutusoru@softvision.ro>
Desc: Merge pull request #19553 from viorelaioia/bug-1008909

Bug 1008909 - Refactor test_inter_app_comm

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https://hg.mozilla.org/integration/gaia-central/rev/51fefd73de3e
Author: Viorela Ioia <viorelaioia@gmail.com>
Desc: Bug 1008909 - Refactor test_inter_app_comm
Bumping manifests a=b2g-bump