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

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https://hg.mozilla.org/integration/gaia-central/rev/8dfc05371d7f
Author: Ben Francis <ben@tola.me.uk>
Desc: Merge pull request #16848 from benfrancis/978371

Bug 978371 - Fix editing bookmark URLs r=vingtetun

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https://hg.mozilla.org/integration/gaia-central/rev/be625f9a3e41
Author: Ben Francis <ben@tola.me.uk>
Desc: Bug 978371 - Fix editing bookmark URLs
Bumping manifests a=b2g-bump