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

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https://hg.mozilla.org/integration/gaia-central/rev/8d2ff92f900d
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #22994 from bebef1987/fix_cost

Bug 1054999 - Fix test test_cost_control_data_alert_mobile after locator...

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https://hg.mozilla.org/integration/gaia-central/rev/8f74801d020f
Author: Bebe <bebe@mozilla.ro>
Desc: Bug 1054999 - Fix test test_cost_control_data_alert_mobile after locator change
Bumping manifests a=b2g-bump