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

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https://hg.mozilla.org/integration/gaia-central/rev/f460a4428b51
Author: Marina <marina.rodrigueziglesias@telefonica.com>
Desc: Merge pull request #26118 from gitmai/bug-1084010-add-Search-traffic-to-system

Bug 1084010 - [Usage][Cost Control] Browser icon should not appear in Mo...
r=salva

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https://hg.mozilla.org/integration/gaia-central/rev/4fb76ed1b119
Author: mai <mri@tid.es>
Desc: Bug 1084010 - [Usage][Cost Control] Browser icon should not appear in Mobile App Usage list
Bumping manifests a=b2g-bump