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

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https://hg.mozilla.org/integration/gaia-central/rev/a8c76559e27e
Author: Michael Henretty <michael.henretty@gmail.com>
Desc: Merge pull request #22678 from mikehenrty/bug-1050861-tornado

Bug 1050861 - Use version 2.4.1 for tornado in gaia unit tests

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https://hg.mozilla.org/integration/gaia-central/rev/cd6e46b1159e
Author: Michael Henretty <michael.henretty@gmail.com>
Desc: Bug 1050861 - Use version 2.4.1 for tornado in gaia unit tests
Bumping manifests a=b2g-bump