Bump node from 18.12 to 20.2 in /services/web (#244)

Bumps node from 18.12 to 20.2.

---
updated-dependencies:
- dependency-name: node
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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services/web/Dockerfile

@@ -1,4 +1,4 @@
-FROM node:18.12 as build
+FROM node:20.2 as build
 
 ARG DOMAIN
 ENV DOMAIN=${DOMAIN}