Thanks for pointing this out.  I performed the deletion in https://osm.org/changeset/168986891.  To delete part of an OSM way, you would select both the way and the cutoff point, use the "split" command, and then delete one of the two ways left after the split.

In the future, if you need a change made to the map but are not sure how to perform it, it's better to create a note with the information (https://wiki.openstreetmap.org/wiki/Notes) than to add dummy data to the map.  Thanks for your contributions!