[Heartbeat] Upgrade node to latest LTS (#40038)

* [Heartbeat] Upgrade node to latest LTS

* Add changelog

CHANGELOG.next.asciidoc

@@ -298,6 +298,7 @@ https://github.com/elastic/beats/compare/v8.8.1\...main[Check the HEAD diff]
 *Heartbeat*
 
 - Added status to monitor run log report.
+- Upgrade node to latest LTS v18.20.3. {pull}40038[40038]
 
 *Metricbeat*
 

dev-tools/packaging/templates/docker/Dockerfile.tmpl

@@ -123,7 +123,7 @@ RUN echo \
 ENV ELASTIC_SYNTHETICS_CAPABLE=true
 ENV TZ=UTC
 ENV SUITES_DIR={{ $beatHome }}/suites
-ENV NODE_VERSION=18.18.2
+ENV NODE_VERSION=18.20.3
 ENV PATH="$NODE_PATH/node/bin:$PATH"
 # Install the latest version of @elastic/synthetics forcefully ignoring the previously
 # cached node_modules, heartbeat then calls the global executable to run test suites
@@ -152,7 +152,7 @@ RUN cd /usr/share/heartbeat/.node \
 RUN chown -R {{ .user }} $NODE_PATH
 USER {{ .user }}
 # If this fails dump the NPM logs
-RUN npm i -g --loglevel verbose --engine-strict @elastic/synthetics@stack_release || sh -c 'tail -n +1 /root/.npm/_logs/* && exit 1'
+RUN npm i -g --loglevel verbose --production --engine-strict @elastic/synthetics@stack_release || sh -c 'tail -n +1 /root/.npm/_logs/* && exit 1'
 RUN chmod ug+rwX -R $NODE_PATH 
 USER root