Many many duplicate locId in output geojson

[lyricnz]

eg for ACT

❯ grep -h locID results/ACT/*.geojson | sort | uniq -c -d | sort -rn | head
 457     "locID": "ChIJGWbSuYjKF2sR-Tf4TBmJdXM",
 445     "locID": "LOC000110299596",
 412     "locID": "LOC000116794801",
 370     "locID": "ChIJ83-j3natF2sRpRYMSup438w",
 349     "locID": "LOC000170481103",
 344     "locID": "LOC000140408442",
 313     "locID": "ChIJeWHPuW-tF2sRe4BApDhPF98",
 310     "locID": "ChIJg4Q9wBZNFmsRVBZubG5dIa0",
 279     "locID": "ChIJA-JUBW-tF2sRiUEs5J_GQiY",
 264     "locID": "LOC000111074697",

This is probably due to the way in which we handle "suggestions" and in particular when there are >1

[lyricnz]

See https://github.com/LukePrior/nbn-upgrade-map/issues/179

[lyricnz]

Total addresses: 14673153 Total duplicates: 2341231

[LukePrior]

Oh damn, I didn't realise it was quite that high...