Bumping gaia.json for 4 gaia-central revision(s)

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https://hg.mozilla.org/integration/gaia-central/rev/2f20db8267c6
Author: Anthony Ricaud <anthony@ricaud.me>
Desc: Revert "Merge pull request #12190 from alivedise/bugzilla/912796/lockscreen-meets-attentionscreen"

This reverts commit 669b4b40972ae008b26270557a393383ae094a2b, reversing
changes made to 6daadc0648db36252fea687f1ceba1de6ad9428d.

This breaks the unit tests.

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https://hg.mozilla.org/integration/gaia-central/rev/53c236ad8594
Author: b2gautomation <jonallengriffin@gmail.com>
Desc: Update gaia-ui-tests.json; Merge pull request #1343 from bebef1987/key

Mirgate e.me search tests to use the onscreen keyboard

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https://hg.mozilla.org/integration/gaia-central/rev/f642926d6149
Author: Anthony Ricaud <anthony@ricaud.me>
Desc: Merge pull request #12217 from Rik/merge-button-887680-clean

Bug 887680 - [User Story] Create a conf call with upto 5 participants r=etienne

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https://hg.mozilla.org/integration/gaia-central/rev/7c60fa5686a2
Author: Anthony Ricaud <anthony@ricaud.me>
Desc: Bug 887680 - [User Story] Create a conf call with upto 5 participants