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

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https://hg.mozilla.org/integration/gaia-central/rev/c2e6e5fb2c84
Author: Salvador de la Puente González <salva@unoyunodiez.com>
Desc: Merge pull request #13948 from gitmai/bug-937240-remove-mindgap

Bug 937240 - [COST CONTROL] Remove the  module mindgap and filtering ope...
r=salva

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https://hg.mozilla.org/integration/gaia-central/rev/f55da1a15374
Author: mai <mri@tid.es>
Desc: Bug 937240 - [COST CONTROL] Remove the  module mindgap and filtering operations of historical data