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

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https://hg.mozilla.org/integration/gaia-2_1/rev/621570cda8c8
Author: viorelaioia <viorela.ioia@softvision.ro>
Desc: Merge pull request #26554 from chirarobert/bug_1106033

Bug 1106033 - [v2.1] Fix test_ftu_skip_tour failure

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https://hg.mozilla.org/integration/gaia-2_1/rev/9015165553e8
Author: Robert Chira <robertchira@P5075.(none)>
Desc: Bug 1106033 - [v2.1] Fix test_ftu_skip_tour failure
Bumping manifests a=b2g-bump