Fix multiuser switch scenario uiAutomation timeout fail

Multiuser switch scenario may cause CPU bond in some
legacy low end platform, it is easily hit UiAutomation
connect timeout issue.

Increase the scenario waiting time to avoid it.

Bug: 177486684
Test: run ShortcutManagerMultiuserTest pass

Change-Id: Ia6bec917fdde15f7839086f9e2af4e88711880e5
2 files changed