Force ctrace for coverage measurement

Author: hynek

pyproject.toml

@@ -163,6 +163,7 @@ filterwarnings = ["once::Warning", "ignore:::pympler[.*]"]
 parallel = true
 branch = true
 source_pkgs = ["attr", "attrs"]
+core = "ctrace"  # currently necessary for 3.14
 
 [tool.coverage.paths]
 source = ["src", ".tox/py*/**/site-packages"]