Drop stop_position matches

[matkoniecz]

if only stop_position is mapped then adding wikidata to it is incorrect, it should be added to not yet mapped stop/station

if both stop position and stop/station is mapped then stop_position match blocks adding wikidata

see

https://osm.wikidata.link/detail/Q2330625/node/484882007 https://osm.wikidata.link/detail/Q2330625/node/6539219984 https://osm.wikidata.link/detail/Q2330625/node/6539244085

for the second case, blocking match in https://osm.wikidata.link/candidates/relation/451266

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stop_position match never improves anything