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

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https://hg.mozilla.org/integration/gaia-central/rev/03ea04a1a24e
Author: Andrew Sutherland <asutherland@asutherland.org>
Desc: Merge pull request #13864 from asutherland/encoding-explosions

Bug 883767 - [Email] Unsupported encoding in some email makes the email client explode. r=asuth

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https://hg.mozilla.org/integration/gaia-central/rev/55b2bfd7f3b7
Author: Andrew Sutherland <asutherland@asutherland.org>
Desc: Bug 883767 - [Email] Unsupported encoding in some email makes the email client explode. r=asuth

propagate https://github.com/mozilla-b2g/gaia-email-libs-and-more/pull/262