Enabled phabricator importer by default

What does this MR do?

Related to: #281610 (closed)

Enable phabricator importer by default with the goal to get more users using it and get more feedback to evolve it.

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
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Security

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