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

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https://hg.mozilla.org/integration/gaia-central/rev/a90ab6c6ba17
Author: James Burke <jrburke@gmail.com>
Desc: Merge pull request #14737 from jrburke/bug950588-email-missing-folder-list

Bug 950588 - [Email][V1.3] Cannot get the folder list while you want to move multiple mails r=gaye

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https://hg.mozilla.org/integration/gaia-central/rev/fc9cf6fdaef3
Author: jrburke <jrburke@gmail.com>
Desc: Bug 950588 - [Email][V1.3] Cannot get the folder list while you want to move multiple mails