Fix an error in debug logging of cloud-what

The `requests.PreparedRequest` may not have any `.body` attribute set.
This happens when unit tests are run, for example. In that case the test
would crash.

src/cloud_what/_base_provider.py

@@ -366,7 +366,7 @@ def _debug_print_http_request(request: requests.PreparedRequest) -> None:
             print(colorize("Request headers:", COLOR.GREEN))
             print(colorize(f"{request.headers}", COLOR.BLUE))
 
-        if os.environ.get("SUBMAN_DEBUG_PRINT_REQUEST_BODY", "") and request.body is not None:
+        if os.environ.get("SUBMAN_DEBUG_PRINT_REQUEST_BODY", "") and hasattr(request, "body"):
             print(colorize("Request body:", COLOR.GREEN))
             print(colorize(f"{request.body}", COLOR.YELLOW))