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

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https://hg.mozilla.org/integration/gaia-2_0/rev/e6e59c4b4c1f
Author: Yuren Ju <yurenju@gmail.com>
Desc: Merge pull request #20398 from yurenju/intermittent-debug

Bug 1022196 - Intermittent build.test.js | Build Integration tests make ... r=testonly
Bumping manifests a=b2g-bump