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

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https://hg.mozilla.org/integration/gaia-1_4/rev/bc86e96d93a7
Author: Michael Henretty <michael.henretty@gmail.com>
Desc: Revert "Merge pull request #17997 from mikehenrty/bug-988737-clear"

This reverts commit 32af2759f67252fa490d1f36f912b73a33481965.
Bumping manifests a=b2g-bump