ci: Fail-fast "npm ci" if deps require unsupported node version (#387)

`+` refactor: Write correct node version in caption

---

When upgrading a dependency to a newer version, it might require a
different node version than before which could be unsupported by the
repo. Unfortunately, this could be easily overseen.

This PR adds the flag --engine-strict to the dependency installation
step during the GH Actions job. Incase such a version requirement
change, this flag will now fail-fast the job which should attract
attention.

Author: maxreichmann

.github/workflows/github-ci.yml

@@ -17,13 +17,13 @@ jobs:
 
     - uses: actions/checkout@v5
 
-    - name: Use Node.js LTS 20.11.0
+    - name: Use Node.js LTS 20.19.5
       uses: actions/setup-node@v6
       with:
         node-version: 20.19.5
 
     - name: Install dependencies
-      run: npm ci
+      run: npm ci --engine-strict # --engine-strict is used to fail-fast if deps require node versions unsupported by the repo
 
     - name: Perform checks and tests
       run: npm test