[test][conftest] Handle multiple calls to beat.core teardown

beat/editor/test/conftest.py

@@ -60,4 +60,10 @@ def test_prefix():
     # corresponding tear down, therefore trigger it manually
     beat_core_test = importlib.import_module("beat.core.test")
     teardown_package = getattr(beat_core_test, "teardown_package")
-    teardown_package()
+
+    try:
+        teardown_package()
+    except FileNotFoundError:
+        # Only needed once because that prefix is generated on call of the
+        # resource_filename of beat.core.test
+        pass