chore: Fix action

Author: fucksophie

.github/workflows/build.yml

@@ -21,6 +21,8 @@ jobs:
         with:
           version: ${{env.EM_VERSION}}
           actions-cache-folder: ${{env.EM_CACHE_FOLDER}}
+      - name: Create build folder
+        run: mkdir -p build
       - name: Build AudioEngine
         run: emcc -std=c++11 -lembind -s ALLOW_MEMORY_GROWTH -s EXPORTED_FUNCTIONS="['_malloc', '_free']" -s AUDIO_WORKLET=1 -s WASM_WORKERS=1 -O3 --emit-tsd audioengine.ts.d -o build/audioengine.js audioengine.cpp
       - name: Upload artifact