Ignore tornado/39462 as there is currently no fix

See tornadoweb/tornado#2981

noxfile.py

@@ -100,7 +100,9 @@ def safety(session: Session) -> None:
     """Scan dependencies for insecure packages."""
     requirements = nox_poetry.export_requirements(session)
     session.install("safety")
-    session.run("safety", "check", f"--file={requirements}", "--bare")
+    # Ignore tornado/39462 as there is currently no fix
+    # See https://github.com/tornadoweb/tornado/issues/2981
+    session.run("safety", "check", f"--file={requirements}", "--bare", "-i", "39462")
 
 
 @nox.session(python=python_versions)