chore(deps): bump node from 21.5.0-alpine to 21.6.0-alpine

Bumps node from 21.5.0-alpine to 21.6.0-alpine.

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

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

Dockerfile

@@ -17,7 +17,7 @@ WORKDIR /app
 # image for creating the documentation
 ######################################
 
-FROM node:21.5.0-alpine as DOCS
+FROM node:21.6.0-alpine as DOCS
 
 # install packages
 RUN apk add --update --no-cache bash make git zsh curl tmux