build(deps): bump node in /docker/modbus-serial

Bumps node from 18.20.8-alpine to 24.8.0-alpine.

---
updated-dependencies:
- dependency-name: node
  dependency-version: 24.8.0-alpine
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

docker/modbus-serial/Dockerfile

@@ -1,5 +1,5 @@
 #### Stage BASE ########################################################################################################
-FROM node:18.20.8-alpine AS base
+FROM node:24.8.0-alpine AS base
 
 # Install tools, create app dir, add user and set rights
 RUN set -ex && \