Python: Use relative file path as run config name

Change-Id: Ifac28b9e4b066ea62b43a7da04b71e2c4317a898
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/python/pythonproject.cpp

@@ -257,6 +257,7 @@ void PythonBuildSystem::triggerParsing()
         newRoot->addNestedNode(std::make_unique<PythonFileNode>(filePath, displayName, fileType));
         if (fileType == FileType::Source) {
             BuildTargetInfo bti;
+            bti.displayName = displayName;
             bti.buildKey = f;
             bti.targetFilePath = filePath;
             bti.projectFilePath = projectFilePath();