This way the net names can be inspected in eeschema and cross-probing works.
Testcases updated for the name changes
CHANGED: all unconnected pins are now included in the netlist with no_connect_ prefixes
This behavior provided shorter net names, but was confusing if
the user gives an explicit strong driver in the subsheet but not
one in the parent sheet.
Testcases updated for net name changes; connectivity is the same
Fixes https://gitlab.com/kicad/code/kicad/-/issues/4201