[BUG]: Use of pybind11::args or pybind11::kw_only results in a Sphinx warning due to the use of *

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What version (or hash if on master) of pybind11 are you using?

3cc7e4258c15a6a19ba5e0b62a220b1a6196d4eb

Problem description

The function initialize_generic in pybind11.h adds the signature of overloads as part of the docs string if show_function_signatures is true. This signature is not marked as code and hence any use of * in that signature are not correctly interpreted by sphinx, causing an "Inline emphasis start-string without end-string" warning.

A minimal fix is changing this line to

signatures += std::regex_replace(std::string(it->signature), std::regex("\\*"), "\\*"); // making sure * are escaped

Alternatively, the name + signature could also be surrounded by a code block or inline code markers.
The nicest IMO would be for the signatures to be presented in the same style that member functions of a class are, though I don't know how that would need to be done.

Reproducible example code

void createBinding(pybind11::module &m) {

  m.def("foo", [&](pybind11::args args) {
    // ...;
  });
}

Is this a regression? Put the last known working version here if it is.

Not a regression

Start in include/pybind11/pybind11.h around line 582, where initialize_generic adds overload signatures when show_function_signatures is enabled. Reproduce the warning with the provided pybind11::args example and inspect how the generated signature is passed to Sphinx. Done means signatures containing * are rendered without an "Inline emphasis start-string without end-string" warning.