pythongh-82378: document the difference between sys.tracebacklimit and the limit arguments

Author: cfbolz

Doc/library/traceback.rst

@@ -42,6 +42,12 @@ The module defines the following functions:
    :term:`file <file object>` or :term:`file-like object` to
    receive the output.
 
+   Note that the meaning of the *limit* parameter is different than the meaning
+   of :const:`sys.tracebacklimit`. Negative *limit* values correspond to
+   positive values of  :const:`sys.tracebacklimit`, whereas the behaviour of
+   positive values of *limit* cannot be achieved with
+   :const:`sys.tracebacklimit`.
+
    .. versionchanged:: 3.5
        Added negative *limit* support.