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

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https://hg.mozilla.org/integration/gaia-1_4/rev/f6d6d9f13f70
Author: viorelaioia <viorelaioia@gmail.com>
Desc: Merge pull request #20566 from bebef1987/gall-update

Bug 1021027 - [Flame] Investigate failure in gallery tests

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https://hg.mozilla.org/integration/gaia-1_4/rev/81a123ae528f
Author: Dylan Chun Wong <d.chunwong@gmail.com>
Desc: Bug 1021027 - [Flame] Investigate failure in gallery tests
Bumping manifests a=b2g-bump