Bumping gaia.json for 2 gaia-central revision(s)

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https://hg.mozilla.org/integration/gaia-central/rev/c96e0e230e9d
Author: Francisco Borja Salguero Castellano <borjasalguero@users.noreply.github.com>
Desc: Merge pull request #12150 from borjasalguero/oslo_actionmenu

Bug 912904 - [System][Dialogs][ActionMenu] Dialogs & Action menus (BB) a...

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https://hg.mozilla.org/integration/gaia-central/rev/53a639c23e19
Author: borjasalguero <fbsc@tid.es>
Desc: Bug 912904 - [System][Dialogs][ActionMenu] Dialogs & Action menus (BB) are not scrolling as expected when there is a large list of items. r=alive,kaze