Rewrite Dockerfile

Add build cache for yarn install command
Remove unnecessary mkdir command

Dockerfile

@@ -1,11 +1,15 @@
 FROM node:16-alpine
-RUN mkdir -p /usr/src/app
-ENV APP_PATH /usr/src/app
-COPY package.json $APP_PATH
-WORKDIR $APP_PATH
-RUN yarn install
-COPY . $APP_PATH
+
+WORKDIR /usr/src/app
+
+COPY yarn.lock package.json .
+
+RUN --mount=type=cache,target=/root/.yarn --mount=type=cache,target=/root/.cache YARN_CACHE_FOLDER=/root/.yarn yarn install
+
+COPY . .
+
 # expose port 3000 for server and 9000 for webpack-dev-server
 EXPOSE 3000 9000
+
 # run start:frontend and start:dev in parallel
 CMD ["yarn", "start:frontend", "start:dev"]