build: updated Dockerfile to use corepack

- cleaned up/optimized command execution

Dockerfile

@@ -1,29 +1,27 @@
-FROM node:lts AS build
-
-WORKDIR /build
+FROM node:lts AS base
 
+RUN corepack enable
 
-RUN npm install -g npm
+FROM base AS build
 
-COPY package.json .
-COPY yarn.lock .
+WORKDIR /build
 
-COPY client/ client/
-COPY server/ server/
+COPY package.json yarn.lock /build/
 
-RUN npx yarn install
+COPY client/ /build/client/
+COPY server/ /build/server/
 
-RUN npx yarn workspace tacos-client run build
+RUN yarn install && yarn workspace tacos-client run build
 
-FROM node:lts
+FROM base AS prod
 
 EXPOSE 3000
+
 CMD ["npm","start"]
-WORKDIR /app
 
-RUN npm install -g npm
+WORKDIR /app
 
 COPY --from=build /build/server/ /app/
 COPY --from=build /build/client/build/ /app/public/
 
-RUN npx yarn install
+RUN yarn install