Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-2_0/rev/bd00ee258331
Author: Carmen Jimenez Cabezas <cjc@tid.es>
Desc: Bug 1022513 - Add unit tests for the vertical homescreen configuration
Bumping manifests a=b2g-bump