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

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https://hg.mozilla.org/integration/gaia-central/rev/902924966a64
Author: viorelaioia <viorela.ioia@softvision.ro>
Desc: Merge pull request #26236 from chirarobert/bug_1100846

Bug 1100846 - [v2.2] Investigate test_sms_with_attachments intermittent ...

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https://hg.mozilla.org/integration/gaia-central/rev/92cff4cbf9bc
Author: Robert Chira <robertchira@P5075.(none)>
Desc: Bug 1100846 - [v2.2] Investigate test_sms_with_attachments intermittent failure
Bumping manifests a=b2g-bump