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

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https://hg.mozilla.org/integration/gaia-central/rev/13b27bbad88e
Author: gasolin <gasolin@gmail.com>
Desc: Merge pull request #25978 from gasolin/issue-1096147

Bug 1096147 - [uitests] Show API version in Bluetooth panel, r=me

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https://hg.mozilla.org/integration/gaia-central/rev/8520c4c20941
Author: gasolin <gasolin@gmail.com>
Desc: Bug 1096147 - [uitests] Show API version in Bluetooth panel
Bumping manifests a=b2g-bump