[fix] #98 fix build not updated if setup.py updated

Makefile

@@ -36,8 +36,9 @@ format:
 	black tests
 	black examples
 
-# build a whell package in dist folder
+# build a wheel package in dist folder
 build:
+	rm -r build/* dist/*
 	python setup.py sdist bdist_wheel
 
 # upload on PyPi repository