Adapt to "tmpl" template repository version 0.4.0 (#15)

Adapted to "tmpl" version 0.4.0 [1] which includes a optimized OS
version matrix strategy for Node based tasks in the CI workflow [2] that
helps to keep the required GitHub Action run minutes for the account of
this repository as small as possible without wasting resources for
unnecessary tasks.

[1]: https://github.com/svengreb/tmpl/releases/tag/v0.4.0
[2]: svengreb/tmpl#46

Resolves GH-14

.github/workflows/ci.yml

@@ -10,9 +10,6 @@ on: [push]
 jobs:
   lint-node:
     runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        node-version: [12.x, 14.x]
     steps:
       - name: Print metadata and context information
         run: |
@@ -21,10 +18,10 @@ jobs:
           echo "Workflow Actor: $GITHUB_ACTOR"
       - name: Checkout repository
         uses: actions/checkout@v2
-      - name: "Setup Node.js version ${{ matrix.node-version }}"
+      - name: "Setup Node.js version 14.x"
         uses: actions/setup-node@v1
         with:
-          node-version: ${{ matrix.node-version }}
+          node-version: "14.x"
       - name: Install Node modules
         run: yarn --frozen-lockfile
       - name: Run linters