move pytest config to pyproject.toml (#2191)

Author: Borda

pyproject.toml

@@ -4,3 +4,12 @@ requires = [
     "wheel"
 ]
 build-backend = "setuptools.build_meta"
+
+
+[tool.pytest.ini_options]
+addopts = [
+    "--strict-markers",
+]
+markers = [
+    "slow: marks tests as slow (deselect with `-m 'not slow'`)",
+]