Latest coverage interfers with tests

Drop coverage, it's not use at the moment.

.github/workflows/main.yml

@@ -32,10 +32,7 @@ jobs:
       - name: "Update pip"
         run: python -m pip install --upgrade pip setuptools wheel
       - name: "Install tox dependencies"
-        run: python -m pip install --upgrade tox tox-gh-actions coverage[toml]
+        run: python -m pip install --upgrade tox tox-gh-actions
       - name: "Run tox for ${{ matrix.python-version }}"
         run: "python -m tox"
-      - name: "Upload coverage to Codecov"
-        uses: "codecov/codecov-action@v1"
-        with:
-          fail_ci_if_error: true
+

tox.ini

@@ -4,17 +4,13 @@ skip_missing_interpreters = true
 
 [testenv]
 commands =
-    coverage run --parallel-mode tests.py
-    coverage combine
-    coverage xml
-    coverage report -m
+    {envpython} {toxinidir}/tests.py
 deps =
     lxml
-    coverage
 
 [testenv:py38]
 # lxml FTBFS because Python sets -Wimplicit-int
-deps = coverage
+deps =
 
 [testenv:black]
 commands = black --check --verbose \
@@ -51,6 +47,6 @@ max-line-length = 98
 python =
     3.6: py36
     3.7: py37
-    3.8: py38, pep8py3, doc
-    3.9: py39, black
-    3.10: py310
+    3.8: py38, pep8py3
+    3.9: py39, doc
+    3.10: py310, black