034561f9cd cli: fix Fatal LevelDB error when specifying -blockfilterindex=basic twice (Harris)
Pull request description:
This PR fixes#17679 by replacing BlockFilterType-vector with a set of the same type to make sure that only unique filter types get inserted.
ACKs for top commit:
MarcoFalke:
ACK 034561f9cd📖
laanwj:
ACK 034561f9cd
fanquake:
ACK 034561f9cd - Tested with `src/bitcoind --blockfilterindex=basic --blockfilterindex=basic`
Tree-SHA512: 64ccec4d23528abfbb564f2b41fb846137875260ce06ea461da12175819985964a1a7442788d5ff7282b5de0c5fd46524d9a793788ee3b876626cbdf05b28c16