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

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https://hg.mozilla.org/integration/gaia-central/rev/a9d774b26329
Author: James Lal <james@lightsofapollo.com>
Desc: Merge pull request #24864 from lightsofapollo/bug-1078976

Bug 1078976 - Add default for BUILDAPP to ./bin/gaia-marionette

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https://hg.mozilla.org/integration/gaia-central/rev/d32db1379e5e
Author: James Lal <james@lightsofapollo.com>
Desc: Bug 1078976 - Add default for BUILDAPP to ./bin/gaia-marionette
Bumping manifests a=b2g-bump