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

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https://hg.mozilla.org/integration/gaia-central/rev/0a7ff1bfe74a
Author: Yi-Fan Liao <begeeben@gmail.com>
Desc: Merge pull request #22818 from begeeben/1049685_ringers_name_overlay_master

Bug 1049685 - [Tarako][Settings] Ringer's name overlay Alerts in Sound setting page, r= Arthur Chen [:arthurcc]

* Workaround for li button in shared/style/button.css. This should be backout once bug 1010675 landed.

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https://hg.mozilla.org/integration/gaia-central/rev/5af6a0749b97
Author: Yi-Fan Liao <begeeben@gmail.com>
Desc: Bug 1049685 - [Tarako][Settings] Ringer's name overlay Alerts in Sound setting page

* Workaround for li button in shared/style/button.css. This should be backout once bug 1010675 landed.
Bumping manifests a=b2g-bump