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

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https://hg.mozilla.org/integration/gaia-central/rev/5b7182e0e489
Author: viorelaioia <viorela.ioia@softvision.ro>
Desc: Merge pull request #25369 from JohanLorenzo/bug-1086269

Bug 1086269 - Add a test to set up a conference call

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https://hg.mozilla.org/integration/gaia-central/rev/62e37df0cec6
Author: Johan Lorenzo <jlorenzo@mozilla.com>
Desc: Bug 1086269 - Add a test to set up a conference call
Bumping manifests a=b2g-bump