Missing internal edges lead to wrong instruction collapsing

[oxidase]

If edges of a segregate intersection are not detected as internal, eg https://www.openstreetmap.org/way/151861700 is not detected as an internal edge

then some instructions can be collapsed twice: in collapseSegregatedTurnInstructions and later in collapseTurnInstructions. The latter collapsing may use incorrect turning angle and this is visible as an unexpected directions modifier SharRight instead of U-Turn:

http://localhost:9966/?z=18&center=48.134556%2C11.522271&loc=48.134680%2C11.522094&loc=48.134744%2C11.522196&hl=en&alt=0

/cc @dgearhart