minor fix in build config

Author: whummer

aws-proxy/Makefile

@@ -32,9 +32,7 @@ dist: venv          ## Create distribution package
 	$(VENV_RUN); python setup.py sdist bdist_wheel
 
 build:              ## Build the extension
-	mkdir -p build
-	cp -r setup.py setup.cfg README.md aws_proxy build/
-	(cd build && python setup.py sdist)
+	$(VENV_RUN); python -m build --no-isolation localstack-extension-aws-proxy --outdir build
 
 enable: $(wildcard ./build/dist/localstack_extension_aws_proxy-*.tar.gz)  ## Enable the extension in LocalStack
 	$(VENV_RUN); \