sagemathgh-40360: Remove sage-sws2rst package and related files
    
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The sage-sws2rst script is used converting old Sage worksheets to
ReStructuredText. These Sage worksheets were removed a couple of years
ago, so I assume it's fine to delete the conversion script as well. In
case someone still has an old notebook lying around, she can use the
version from pypi https://pypi.org/project/sage-sws2rst/.


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preview.

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URL: sagemath#40360
Reported by: Tobias Diez
Reviewer(s): Dima Pasechnik

Author: Release Manager

src/doc/en/prep/Logging-On.rst

@@ -54,7 +54,7 @@ the third option to "export" them will not make sense.
 The legacy SageNB has been retired in Sage 9.1.
 Please use the Jupyter notebook.
 Old SageNB worksheets can be converted to Jupyter notebooks
-using the `sage --notebook=export`_ command or to RST
+using the ``sage --notebook=export`` command or to RST
 using the `sage-sws2rst <https://pypi.org/project/sage-sws2rst/>`_ package.
 
 Jupyter will bring you to a screen