Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/a669219e4428
Author: KWierso <kwierso@gmail.com>
Desc: Revert "Bug 968081 - [Settings][L10n] Localize WiFi hotspot security type info. r=arthurcc" for gaia unit test failures

This reverts commit 25fcf9ebe4d95856d50959fb0ada93b63bc7a5eb.
Bumping manifests a=b2g-bump