Bumping gaia.json for 2 gaia-1_2 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_2/rev/cda953298ca6
Author: James Lal <james@lightsofapollo.com>
Desc: Merge pull request #12693 from lightsofapollo/v1.2-green-unit-tets

skip mobile_operator_test in v1.2 only a=test-only

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https://hg.mozilla.org/integration/gaia-1_2/rev/3e4625ca7f0f
Author: James Lal <james@lightsofapollo.com>
Desc: skip mobile_operator_test in v1.2 only a=test-only