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

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https://hg.mozilla.org/integration/gaia-central/rev/2378fce8fbfa
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #20612 from AndreiH/bug_1026456

Bug 1026456 - [v2.1] Xfail test_ftu_skip_tour.TestFtu with Bug 1024470

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https://hg.mozilla.org/integration/gaia-central/rev/c110ab03f036
Author: Andrei Hutusoru <andreihutusoru@P5069.(none)>
Desc: Bug 1026456 - [v2.1] Xfail test_ftu_skip_tour.TestFtu with Bug 1024470
Bumping manifests a=b2g-bump