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

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https://hg.mozilla.org/integration/gaia-central/rev/6d9439660ed7
Author: viorelaioia <viorela.ioia@softvision.ro>
Desc: Merge pull request #26414 from chirarobert/bug_1096915

Bug 1096915 - Add a test to re-dial the last MO number by pressing the c...

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https://hg.mozilla.org/integration/gaia-central/rev/d54c77a626be
Author: Robert Chira <robertchira@P5075.(none)>
Desc: Bug 1096915 - Add a test to re-dial the last MO number by pressing the call button twice
Bumping manifests a=b2g-bump