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

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https://hg.mozilla.org/integration/gaia-central/rev/5e4fffbaee8e
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #16701 from zacc/bug_977046

Bug 977046 - On device testing, cleanup cache and local webapps between ...

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https://hg.mozilla.org/integration/gaia-central/rev/bddcb4867d40
Author: Zac Campbell <zcampbell@mozilla.com>
Desc: Bug 977046 - On device testing, cleanup cache and local webapps between b2g restart
Bumping manifests a=b2g-bump