IDE-289 Fix import actor from local project

[Frajhamster]

In this story the button "Import from local" has been added back and its functionality has been fixed.

Jira Ticket: https://catrobat.atlassian.net/browse/IDE-289

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[sonarqubecloud]

Quality Gate failed

Failed conditions
C Maintainability Rating on New Code (required ≥ A)

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