Do not use cmake --config for single configuration generators

Signed-off-by: Jose Luis Rivero <[email protected]>

Author: j-rivero

tutorials/23_topic_statistics.md

@@ -79,6 +79,9 @@ For running the example, build the binaries in the example directory:
 git clone https://github.com/gazebosim/gz-transport -b gz-transport14
 cd gz-transport/example
 cmake -S . -B build
+# For UNIX
+cmake --build build --parallel
+# For Windows
 cmake --build build --config release --parallel
 ```