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

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https://hg.mozilla.org/integration/gaia-central/rev/c7c667992e1c
Author: Jan Keromnes <janx@linux.com>
Desc: Merge pull request #17204 from jankeromnes/securityhud

Bug 983710 - Add a "Security issues" category to the Developer HUD. r=21

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https://hg.mozilla.org/integration/gaia-central/rev/ab0ab153bca4
Author: Jan Keromnes <janx@linux.com>
Desc: Bug 983710 - Add a "Security issues" category to the Developer HUD. r=21
Bumping manifests a=b2g-bump