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

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https://hg.mozilla.org/integration/gaia-central/rev/20f334a847cb
Author: Andrew Sutherland <asutherland@asutherland.org>
Desc: Merge pull request #25951 from asutherland/email-compose-normalize-newlines

Bug 1091295 - [email] normalize newlines in composer. r=jrburke

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https://hg.mozilla.org/integration/gaia-central/rev/0d28f12eed90
Author: Andrew Sutherland <asutherland@asutherland.org>
Desc: Bug 1091295 - [email] normalize newlines in composer. r=jrburke

land https://github.com/mozilla-b2g/gaia-email-libs-and-more/pull/352

Failure to normalize newlines in composed messages. May cause some SMTP servers
(ex: qmail) to refuse to send mail with a 451 error.
Bumping manifests a=b2g-bump