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

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https://hg.mozilla.org/integration/gaia-central/rev/214aa4fb3a3f
Author: James Burke <jrburke@gmail.com>
Desc: Merge pull request #23228 from awiss/bug1057277-signature-button

Bug 1057277 - [Email][Signature] Signature text displayed different with UX specification r=jrburke

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https://hg.mozilla.org/integration/gaia-central/rev/7e327383d8ab
Author: Alex Wissmann <awiss@wharton.upenn.edu>
Desc: Bug 1057277 - [Email][Signature] Signature text displayed different with UX specification
Bumping manifests a=b2g-bump