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

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https://hg.mozilla.org/integration/gaia-central/rev/1ad040b490a7
Author: Fernando Jiménez Moreno <ferjmoreno@gmail.com>
Desc: Merge pull request #16672 from ferjm/bug955945.coppa

Bug 955945 - Implement age verification screens for FxA Signup. r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/6c4a067d7285
Author: Fernando Jiménez <ferjmoreno@gmail.com>
Desc: Bug 955945 - Implement age verification screens for FxA Signup. r=alive
Bumping manifests a=b2g-bump