ci: Include hidden files in artifact build (#175)

* ci: Bump download-artifact from v3 to v4

* ci: Fix coverage data upload

Author: mrbazzan

.github/workflows/test.yml

@@ -41,7 +41,8 @@ jobs:
     - name: Upload coverage data
       uses: actions/upload-artifact@v4
       with:
-        name: coverage-data
+        name: coverage-data-${{ matrix.python-version }}
+        include-hidden-files: true
         path: '.coverage.*'
 
   coverage:
@@ -59,9 +60,10 @@ jobs:
         run: python -m pip install --upgrade coverage[toml]
 
       - name: Download data
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
-          name: coverage-data
+          pattern: coverage-data-*
+          merge-multiple: true
 
       - name: Combine coverage
         run: |