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

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https://hg.mozilla.org/integration/gaia-central/rev/3af4c3fce908
Author: Greg Weng <snowmantw@gmail.com>
Desc: Merge pull request #18061 from snowmantw/issue992281

Bug 992281 - [B2G][Dialer] When a call is ended while the proximity sensor is covered device will return to lockscreen

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https://hg.mozilla.org/integration/gaia-central/rev/141fe467558b
Author: Greg Weng <snowmantw@gmail.com>
Desc: Bug 992281 - [B2G][Dialer] When a call is ended while the proximity sensor is covered device will return to lockscreen
Bumping manifests a=b2g-bump