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

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https://hg.mozilla.org/integration/gaia-central/rev/45d75251805a
Author: Fabrice Desré <fabrice@desre.org>
Desc: Merge pull request #13475 from fabricedesre/skip-lockscreen-desktop

Bug 891882 - skip lockscreen test on deskop until the stars align r=me

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https://hg.mozilla.org/integration/gaia-central/rev/b6f934d365c7
Author: Fabrice Desré <fabrice@desre.org>
Desc: Bug 891882 - skip lockscreen test on deskop until the stars align r=me