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

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https://hg.mozilla.org/integration/gaia-central/rev/572960d218bd
Author: Gareth Aye <gaye@mozilla.com>
Desc: Merge pull request #24527 from gaye/bump-test-agent-in-dev_apps-to-0.25.0

Bug 1068236 - Bump test agent to 0.25.0

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https://hg.mozilla.org/integration/gaia-central/rev/e9d29bb7e00c
Author: gaye <gaye@mozilla.com>
Desc: Bug 1068236 - Bump test agent to 0.25.0
Bumping manifests a=b2g-bump