Update to Node 20

This should fix the memleak issue we are seeing
See vercel/next.js#49929

.nvmrc

@@ -1 +1 @@
-16
+20

Dockerfile

@@ -1,7 +1,7 @@
 # Copied from https://github.com/vercel/next.js/tree/canary/examples/with-docker
 
 # Install dependencies only when needed
-FROM node:16-alpine AS deps
+FROM node:20-alpine AS deps
 # Check https://github.com/nodejs/docker-node/tree/b4117f9333da4138b03a546ec926ef50a31506c3#nodealpine to understand why libc6-compat might be needed.
 RUN apk add --no-cache libc6-compat
 WORKDIR /app
@@ -17,7 +17,7 @@ RUN \
 
 
 # Rebuild the source code only when needed
-FROM node:16-alpine AS builder
+FROM node:20-alpine AS builder
 WORKDIR /app
 COPY --from=deps /app/node_modules ./node_modules
 COPY . .
@@ -33,7 +33,7 @@ RUN yarn build
 # RUN npm run build
 
 # Production image, copy all the files and run next
-FROM node:16-alpine AS runner
+FROM node:20-alpine AS runner
 WORKDIR /app
 
 ENV NODE_ENV production