Add CMake Options to Disable pybind/swig

[mjcarroll]

Environment

• OS Version: Windows (but affects all)
• Source or binary build? Source

Description

We fail the build in gz-math and sdformat when python or ruby bindings aren't generated, even though these could be considered optional components.

This is particularly an issue on Windows, where we don't prompt users to install all dependencies required for bindings, causing the build to fail by default.

In general, we should provide knobs to opt out of optional behavior, and recommend using them on platforms where language bindings are inconvenient (aka Windows)

• gz-math Add option to skip pybind11 and SWIG gz-math#480
• sdformat Add option to skip python bindings sdformat#1106
• gz-sim Add option to disable building python bindings gz-sim#1637