Mark code used only in tests as "Potentionaly Redundant"

I had an method in service that was covered by tests.
When controller that used that method was deleted, IntelliJ still shows that this method is used.
But actually it was used only by tests and I don't need it now.
Could you make some inspection for this cases?

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*Imported from [IDEA-128600](https://youtrack.jetbrains.com/issue/IDEA-128600) · Type: Feature · Votes: 3*
*Comments, attachments, dates and reporter are not part of the export — follow the link above for the full history.*

Start by reviewing the plugin's existing inspection implementations and the imported IDEA-128600 issue, since no source files or tests are identified here. The work is complete when code referenced only from tests is identified and marked as "Potentially Redundant," with coverage for the reported controller-deletion scenario.

Written by the indexing model from the issue text.