Added logging-not-lazy message example (#6619)

Co-authored-by: Pierre Sassoulas <pierre.sassoulas@gmail.com>
Co-authored-by: Daniël van Noord <13665637+DanielNoord@users.noreply.github.com>

Author: 3 people

doc/data/messages/l/logging-not-lazy/bad.py

@@ -0,0 +1,7 @@
+import logging
+
+try:
+    function()
+except Exception as e:
+    logging.error('Error occured: %s' % e)  # [logging-not-lazy]
+    raise

doc/data/messages/l/logging-not-lazy/details.rst

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+Another reasonable option is to use f-strings. If you want to do that, you need to enable
+``logging-not-lazy`` and disable ``logging-fstring-interpolation``.

doc/data/messages/l/logging-not-lazy/good.py

@@ -0,0 +1,7 @@
+import logging
+
+try:
+    function()
+except Exception as e:
+    logging.error('Error occured: %s', e)
+    raise

doc/data/messages/l/logging-not-lazy/related.rst

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+- `Logging variable data <https://docs.python.org/3/howto/logging.html#logging-variable-data>`_
+- `Rationale <https://stackoverflow.com/questions/34619790>`_