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

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https://hg.mozilla.org/integration/gaia-2_0/rev/8759fb4519c0
Author: Ed Morley <emorley@mozilla.com>
Desc: Revert "Bug 1027144 - Re-enable test_homescreen_move_app.py" for intermittent test failures

This reverts commit d7fd03c94aaf0791ba4c68753230a08b4ed050cd.
Bumping manifests a=b2g-bump