Repair colorama wrapping on non-Windows platforms

The wrap_stream_for_windows() function calls
colorama.initialise.wrap_stream() function to apply colorama's magic to
wrapper to the output stream. Except this wrapper is only applied on
Windows platforms that need it, otherwise the original stream is
returned as-is.

The colorama wrapped stream lacks a detach() method, so a no-op lambda
was being assigned to the wrapped stream.

The problem is that the no-op lambda was being assigned unconditionally
whether or not colorama actually returns a wrapped stream, thus
replacing the original TextIOWrapper's detach() method. Replacing the
detach() method with a no-op lambda is the root cause of the problem
observed in psf#1664.

The solution is to only assign the no-op detach() method if the stream
lacks its own detach() method.

Repairs psf#1664

src/black/__init__.py

@@ -880,7 +880,8 @@ def wrap_stream_for_windows(
 
         # wrap_stream returns a `colorama.AnsiToWin32.AnsiToWin32` object
         # which does not have a `detach()` method. So we fake one.
-        f.detach = lambda *args, **kwargs: None  # type: ignore
+        if not hasattr(f, "detach"):
+            f.detach = lambda: None  # type: ignore
     except ImportError:
         pass