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

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https://hg.mozilla.org/integration/gaia-2_1/rev/99fa6b93f914
Author: Sam Foster <sam@sam-i-am.com>
Desc: Merge pull request #25554 from sfoster/tm-early-filter-bg-bug-1089615

Bug 1089615 - Fade to white background when showing browser-windows switcher. r=etienne, a=fabrice

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https://hg.mozilla.org/integration/gaia-2_1/rev/705d65007c44
Author: Sam Foster <sfoster@mozilla.com>
Desc: Bug 1089615 - Fade to white background when showing browser-windows switcher. r=etienne

* Apply filtered class on task manager earlier
* Pass filter in cardviewbeforeshow event to enable fade out to white in homescreen.
Bumping manifests a=b2g-bump