style: fix isort config

`isort` was misconfigured to only touch `*.{pyw,pyi}` files.

This patch fixes isort config so that it actually does sort imports.

It also removes the attempt to ignore the test directory.

setup.cfg

@@ -46,29 +46,30 @@ follow_imports = skip
 profile = black
 py_version = 37
 line_length = 88
+src_paths=rdflib,test
 supported_extensions =
     pyw
     pyi
+    py
 skip =
-    .eggs         # exclude a few common directories in the
-    .git          # root of the project
-    .hg
-    .mypy_cache
-    .pytest_cache
-    .tox
-    .venv
-    .github
-    _build
-    htmlcov
-    benchmarks
-    examples       # No need to Black examples
-    test           # Tests are a mess, don't black them
-    test_reports
-    rdflib.egg-info
-    buck-out
-    build
-    dist
-    venv
+    .eggs,         # exclude a few common directories in the
+    .git,          # root of the project
+    .hg,
+    .mypy_cache,
+    .pytest_cache,
+    .tox,
+    .venv,
+    .github,
+    _build,
+    htmlcov,
+    benchmarks,
+    examples,       # No need to Black examples
+    test_reports,
+    rdflib.egg-info,
+    buck-out,
+    build,
+    dist,
+    venv,
 
 [tool:pytest]
 addopts =