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

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https://hg.mozilla.org/integration/gaia-2_0/rev/40e950649487
Author: Ryan VanderMeulen <ryanvm@gmail.com>
Desc: Merge pull request #25519 from luke-chang/1079129_v2.0_fullscreen_prompt_overlay_lockscreen

Bug 1079129 - [Woodduck] Lock screen is hidden by full screen prompt message

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https://hg.mozilla.org/integration/gaia-2_0/rev/c164e2ea47ee
Author: Luke Chang <lchang@mozilla.com>
Desc: Bug 1079129 - [Woodduck] Lock screen is hidden by full screen prompt message
Bumping manifests a=b2g-bump