print error message to stderr

Co-authored-by: C Fraire <[email protected]>

Author: Vladimir Kotal

dev/main

@@ -32,7 +32,7 @@ if [[ "$TRAVIS_OS_NAME" == "windows" ]]; then
 
 	PYTHON_PATH="/c/Python39"
 	if [[ ! -d $PYTHON_PATH ]]; then
-		echo "Not a directory: $PYTHON_PATH"
+		>&2 echo "Not a directory: $PYTHON_PATH"
 		exit 1
 	fi
 	# needs to be before the default Python 2