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

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https://hg.mozilla.org/integration/gaia-central/rev/e1b59fc687a5
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Merge pull request #24061 from etiennesegonzac/bug-1043870-homescreen-integration-back

Bug 1043870 - reviving the homescreen navigation reflow test. r=21

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https://hg.mozilla.org/integration/gaia-central/rev/9b40a5042ef0
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Bug 1043870 - reviving the homescreen navigation reflow test.
Bumping manifests a=b2g-bump