doc: remove the last :mod: annotations inside "warning" blocks
Our doc checks do not like that construct, even though newer versions
of Sphinx support it. Drop it for now.
@@ -58,10 +58,10 @@ from a security perspective.
arbitrary code during unpickling**. Never unpickle data that could have come
from an untrusted source, or that could have been tampered with.
- Consider signing data with :mod:`hmac` if you need to ensure that it has not
+ Consider signing data with an HMAC if you need to ensure that it has not
been tampered with.
- Safer deserialization approaches, such as reading :mod:`json` directly,
+ Safer deserialization approaches, such as reading JSON directly,
may be more appropriate if you are processing untrusted data.
