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

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https://hg.mozilla.org/integration/gaia-central/rev/ef5e289aee34
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #13848 from singhkaran/933817

Bug 933817 - Removed all marketplace tests (excluding smoketest) and its...

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https://hg.mozilla.org/integration/gaia-central/rev/4569e075fdd6
Author: Karan <karan.basi@mail.utoronto.ca>
Desc: Bug 933817 - Removed all marketplace tests (excluding smoketest) and its app folder