Remove outdated comment in log config

The now-removed comment was introduced in
#8040, and referenced
a "twisted" logging handler. That handler has since been removed
from the file, so the associated comment is no longer necessary.

docs/sample_log_config.yaml

@@ -68,9 +68,7 @@ root:
     # Write logs to the `buffer` handler, which will buffer them together in memory,
     # then write them to a file.
     #
-    # Replace "buffer" with "console" to log to stderr instead. (Note that you'll
-    # also need to update the configuration for the `twisted` logger above, in
-    # this case.)
+    # Replace "buffer" with "console" to log to stderr instead.
     #
     handlers: [buffer]
 

synapse/config/logger.py

@@ -117,9 +117,7 @@
     # Write logs to the `buffer` handler, which will buffer them together in memory,
     # then write them to a file.
     #
-    # Replace "buffer" with "console" to log to stderr instead. (Note that you'll
-    # also need to update the configuration for the `twisted` logger above, in
-    # this case.)
+    # Replace "buffer" with "console" to log to stderr instead.
     #
     handlers: [buffer]