Bumping gaia.json for 2 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/accec2f4e2c8
Author: Gregor Wagner <anygregor@gmail.com>
Desc: Merge pull request #14479 from gregorwagner/disable

No Bug - Disable intermittent failures

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https://hg.mozilla.org/integration/gaia-central/rev/108ef7a4ce0d
Author: Gregor Wagner <anygregor@gmail.com>
Desc: Disable failing tests