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

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https://hg.mozilla.org/integration/gaia-central/rev/239410962285
Author: BavarianTomcat <tomcat@mozilla.com>
Desc: Revert "Bug 982839 - Write a test to protect against the regression seen in bug 981804 (navigate out of fullscreen video)" for f2 test failures

This reverts commit 801300deb395acf4a1a61c511a63969e3aac4c83.
Bumping manifests a=b2g-bump