Simplify traceback from subprocess (#491)

webviz_config/_build_webviz.py

@@ -56,12 +56,9 @@ def build_webviz(args: argparse.Namespace) -> None:
             if subprocess.call(  # nosec
                 [sys.executable, "copy_data.py"], cwd=build_directory
             ):
-                raise RuntimeError(
-                    "Something went wrong. This is probably "
-                    "not related to the webviz plugin framework, but more "
-                    "likely one of the included plugins in your configuration. "
-                    "See exact error message and traceback above."
-                )
+                # We simply exit here with a non-zero status in order to not clutter
+                # the subprocess traceback with unnecessary information
+                sys.exit(1)
 
             (build_directory / "copy_data.py").unlink()