Bump node from 18.17.1 to 21.6.1

Bumps node from 18.17.1 to 21.6.1.

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

Signed-off-by: dependabot[bot] <support@github.com>

Dockerfile

@@ -1,4 +1,4 @@
-FROM node:18.17.1
+FROM node:21.6.1
 
 RUN apt-get update && \
     apt-get -y clean && \