Repeating SourceFolder fix (#1073)

In case of repeating SourceFolders action would not be shown.
From now it takes first SourceFolder with the same virtual file source
root

Author: Domonion

utbot-intellij/src/main/kotlin/org/utbot/intellij/plugin/ui/actions/GenerateTestsAction.kt

@@ -61,7 +61,7 @@ class GenerateTestsAction : AnAction(), UpdateInBackground {
                 val module = ModuleUtil.findModuleForFile(srcSourceRoot, project) ?: return null
                 val matchingRoot = ModuleRootManager.getInstance(module).contentEntries
                     .flatMap { entry -> entry.sourceFolders.toList() }
-                    .singleOrNull { folder -> folder.file == srcSourceRoot }
+                    .firstOrNull { folder -> folder.file == srcSourceRoot }
                 if (srcMembers.isEmpty() || matchingRoot == null || matchingRoot.rootType.isForTests) {
                     return null
                 }