fix missing dist dir make issue

Makefile

@@ -2,6 +2,7 @@
 
 build: clean
 	@echo "======================== Building Binary ======================="
+	mkdir -p dist
 	cp wfa.js dist/wfa.js
 	GOOS=js GOARCH=wasm CGO_ENABLED=0 tinygo build -panic=trap -no-debug -opt=s -target=wasm -o dist/wfa.wasm .