VS Code settings: Remove some deprecated linters and formatters

Using these tools via the Pylance extension is deprecated. The equivalent
functionality is now available through dedicated VS Code extensions.
See:
  https://aka.ms/AAlgvkb.
  https://marketplace.visualstudio.com/items?itemName=ms-python.black-formatter

Note: Keeping the Pylance's mypy linting for now as it seems to behave better.

.vscode/settings.json

@@ -9,16 +9,15 @@
   "python.analysis.extraPaths": [
     "./stubs"
   ],
-  "python.formatting.provider": "black",
   "python.linting.enabled": true,
-  "python.linting.flake8Enabled": false,
   "python.linting.mypyEnabled": true,
-  "python.linting.pydocstyleEnabled": false,
-  "python.linting.pylintEnabled": false,
   "python.testing.pytestArgs": [
     "-vv",
     "-nauto",
     "tests"
   ],
-  "python.testing.pytestEnabled": true
+  "python.testing.pytestEnabled": true,
+  "[python]": {
+    "editor.defaultFormatter": "ms-python.black-formatter"
+  },
 }