fix: Upgrade node version in backend to try and fix build failure

Author: trillium

backend/Dockerfile.prod

@@ -1,12 +1,12 @@
-FROM node:18.12.0 AS api-builder
+FROM node:20.9.0 AS api-builder
 RUN mkdir /srv/backend
 WORKDIR /srv/backend
 RUN mkdir -p node_modules
 COPY package.json yarn.lock ./
 RUN yarn install --pure-lockfile
 COPY . .
 
-FROM node:18.12.0-slim AS api-production
+FROM node:20.9.0-slim AS api-production
 EXPOSE 4000
 USER node
 WORKDIR /srv/backend