Draft: Fix Draft_Snap_Intersection for self-intersecting objects

[Roy-043]

This is a followup of a previous PR of mine (#5202). Removing the last object from the self.lastObj list prevents the detection of intersections of self-intersecting objects.

This was reported on the Forum. But I can't find the actual topic right now.

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[freecadci]

for feature branch PR_6780. Pipeline 522630656 was triggered at f86fa72. All CI branches and pipelines.

[Roy-043]

Found the Forum topic:
https://forum.freecadweb.org/viewtopic.php?f=3&t=67999

[freecadci]

for feature branch PR_6780. Pipeline 523000225 was triggered at f86fa72. All CI branches and pipelines.

[donovaly]

Thanks!