Merge pull request #2570 from Mytic2330/3.0-patch3

Fixed Connection closed when exporting a running project

gns3server/api/routes/controller/projects.py

@@ -330,6 +330,9 @@ async def export_project(
     Required privilege: Project.Audit
     """
 
+    if project.is_running():
+        raise ControllerError("Project must be stopped in order to export it")
+
     compression_query = compression.lower()
     if compression_query == "zip":
         compression = zipfile.ZIP_DEFLATED