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

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https://hg.mozilla.org/integration/gaia-central/rev/a218828aaed6
Author: James Lal <james@lightsofapollo.com>
Desc: Update taskgraph.json

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https://hg.mozilla.org/integration/gaia-central/rev/fae92816e261
Author: James Lal <james@lightsofapollo.com>
Desc: Update taskgraph.json
Bumping manifests a=b2g-bump