Add support for Windows

[bryanhuhta]

Currently, we don't support Windows because of our usage of dynamic labels. The DataDog profiler doesn't support dynamic labels on Windows:

https://github.com/DataDog/pprof-nodejs/blob/e7d3e053d9816e64710533738ff827c0301b82fe/bindings/profilers/wall.cc#L33

The DD_WALL_USE_SIGPROF enables dynamic labels and if it is disabled, it throws an error here:

https://github.com/DataDog/pprof-nodejs/blob/e7d3e053d9816e64710533738ff827c0301b82fe/bindings/profilers/wall.cc#L609-L611

We always enable withContexts in or SDK:

pyroscope-nodejs/src/profilers/wall-profiler.ts

Line 88 in e2d157c

withContexts: true,

We might be able to support Windows by disabling this configuration when we detect a Windows host, or by providing a way for users to turn it off. At the very least, we should provide a gentler failure case which is more helpful for users.

See #85 for an example of the SDK not working on Windows.

[simonswine]

A good first step might also be to not break the application when running on windows, even if the profiler doens't work/run at all.

I also think we probably should have caught that ourselves by having a test for other OSes than linux (relates to #86)