Use coverage directly instead of dwas for reporting coverage

We will want to compiel coverage from multiple OSs, which we do not
handle normally otherwise. As such, let's just use coverage, it's going
to be faster too

.github/workflows/ci.yml

@@ -141,7 +141,7 @@ jobs:
           path: ${{ env.JUNIT_REPORT_PATH }}/junit-${{ matrix.os }}-${{ matrix.python }}.xml
           retention-days: 7
 
-  coverage:
+  report:
     runs-on: ubuntu-latest
     needs: test
     if: always()
@@ -154,37 +154,21 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: ${{ env.DEFAULT_PYTHON }}
-          cache: pip
 
-      # FIXME: we should take dwas from pypi once it's published
-      - name: Install dwas
-        run: python -m pip install .
+      - name: Install package dependencies
+        run: pip install tabulate
 
-      - name: Download generated coverage files
+      - name: Download junit reports
         uses: actions/download-artifact@v4
         with:
           merge-multiple: true
-          pattern: coverage-*
-          path: .dwas/cache
-
-      - name: Generate coverage report
-        run: dwas --verbose --only coverage
-
-      - name: Upload coverage to codecov
-        uses: codecov/codecov-action@v3
-        with:
-          files: ./_artifacts/coverage/coverage.xml
-          fail_ci_if_error: true
-          verbose: true
+          pattern: junit-*
+          path: reports/
 
-      - name: Save coverage report
-        uses: actions/upload-artifact@v4
-        with:
-          name: coverage [html]
-          path: _artifacts/coverage/html
-          retention-days: 7
+      - name: Generate summary
+        run: python .github/scripts/summary.py reports/*.xml > "${GITHUB_STEP_SUMMARY}"
 
-  report:
+  coverage:
     runs-on: ubuntu-latest
     needs: test
     if: always()
@@ -197,19 +181,43 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: ${{ env.DEFAULT_PYTHON }}
+          cache: pip
 
-      - name: Install package dependencies
-        run: pip install tabulate
+      - name: Install coverage
+        run: python -m pip install coverage[toml]
 
-      - name: Download junit reports
+      - name: Download generated coverage files
         uses: actions/download-artifact@v4
         with:
           merge-multiple: true
-          pattern: junit-*
+          pattern: coverage-*
           path: reports/
 
-      - name: Generate summary
-        run: python .github/scripts/summary.py reports/*.xml > "${GITHUB_STEP_SUMMARY}"
+      - name: Combine coverage files
+        run: coverage combine reports/*/*/coverage
+
+      - name: Generate coverage summary
+        run: coverage report --format=markdown --show-missing | tee "${GITHUB_STEP_SUMMARY}"
+
+      - name: Generate xml coverage
+        run: coverage xml -o _artifacts/coverage.xml
+
+      - name: Upload coverage to codecov
+        uses: codecov/codecov-action@v3
+        with:
+          files: ./_artifacts/coverage.xml
+          fail_ci_if_error: true
+          verbose: true
+
+      - name: Generate html coverage
+        run: coverage html --directory _artifacts/coverage/html
+
+      - name: Save coverage report
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage [html]
+          path: _artifacts/coverage/html
+          retention-days: 7
 
   twine:
     runs-on: ubuntu-latest