Already created test source root is not found in Idea project

[EgorkaKulikov]

Description

Already created test source root is not found in Idea project and is marked with "will be installed" label.

To Reproduce

• Create pure Idea project
• Create standard source root utbot_tests
• Open a dialog again

Actual behavior

Already created source root is still marked with "will be installed" label.

Visual proofs (screenshots, logs, images)

[EgorkaKulikov]

I created a clear project with both JDK 8 and JDK 11 and did not manage to reproduce the problem.

[EgorkaKulikov]

Anyway, I still reproduce this problem on the attached project, that does not seem to be broken.
kdvfkjdvgfkjvgf.zip

FYI @Vassiliy-Kudryashov @alisevych