🔥 Drop --strict from the pytest config

The `--strict` option has been deprecated in v6.2.0 and will probably
resurface at some point in the future but at the moment it's
recommended to use `--strict-markers` instead, which is already
present.

So this change just comments out `--strict` for pytest runs not to
fail in the CI or dev envs.

Ref:
* pytest-dev/pytest#7530
* pytest-dev/pytest#7985

pytest.ini

@@ -11,7 +11,10 @@ addopts =
     --junitxml=.test-results/pytest/results.xml
 
     # Fail on non-existing markers:
-    --strict
+    # * Deprecated since v6.2.0 but may be reintroduced later covering a
+    #   broader scope:
+    # --strict
+    # * Exists since v4.5.0 (advised to be used instead of `--strict`):
     --strict-markers
 
     # `pytest-cov`: