Migrate coverage reporting to GitHub Actions (#454)

Travis seems to be going away from supporting Open Source Software for
free and their proceedure to gaining free tokens is getting harder and
hander to find for each year that passes.  Remove Travis CI integration
and migrate the coverage reporting previously provided by the Travis
build over to the GitHub Actions.

.github/workflows/node.js.yml

@@ -25,7 +25,17 @@ jobs:
     - run: wget -q -O factorio.tar.gz https://www.factorio.com/get-download/latest/headless/linux64 && tar -xf factorio.tar.gz && rm factorio.tar.gz
     - run: npx lerna bootstrap --hoist
     - run: npx lerna run build
-    - run: npm test
+    - name: Run tests
+      if: ${{ matrix.node-version != '12.x' }}
+      run: npm test
+    - name: Run coverage
+      if: ${{ matrix.node-version == '12.x' }}
+      run: npm run ci-cover
+    - name : Upload coverage to Codecov
+      if: ${{ matrix.node-version == '12.x' }}
+      uses: codecov/codecov-action@v2
+      with:
+        files: ./coverage/lcov.info
 
   lint:
     runs-on: ubuntu-latest