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

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https://hg.mozilla.org/integration/gaia-1_4/rev/4cfab1e324a2
Author: Ghislain 'Aus' Lacroix <aus@noiseport.org>
Desc: Merge pull request #20162 from nullaus/bug1009780

bug 1009780 - Improve open mechanism for downloads.
Bumping manifests a=b2g-bump