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

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https://hg.mozilla.org/integration/gaia-central/rev/0784b81a26a1
Author: gitmai <mri@tid.es>
Desc: Merge pull request #15902 from gitmai/bug-959206-CC-DSDS-FTE-not-close-when-change-simcard

Bug 959206 - [CostControl] [DSDS] If device has two SIM cards inserted (...
r=salva

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https://hg.mozilla.org/integration/gaia-central/rev/d828ee28dcd4
Author: mai <mri@tid.es>
Desc: Bug 959206 - [CostControl] [DSDS] If device has two SIM cards inserted (one SIM not configured in cost control and other configured) always appear FTE in cost control
Bumping manifests a=b2g-bump