add assertion for number of block filter indexes (currently just one)

Co-authored-by: hodlinator <172445034+hodlinator@users.noreply.github.com>

Author: svanstaa

src/node/caches.cpp

@@ -71,6 +71,7 @@ CacheSizes CalculateCacheSizes(const ArgsManager& args, size_t n_indexes)
     index_sizes.tx_index = std::min(total_cache * 10 / 100, args.GetBoolArg("-txindex", DEFAULT_TXINDEX) ? MAX_TX_INDEX_CACHE : 0);
     index_sizes.txospender_index = std::min(total_cache * 5 / 100, args.GetBoolArg("-txospenderindex", DEFAULT_TXOSPENDERINDEX) ? MAX_TXOSPENDER_INDEX_CACHE : 0);
     if (n_indexes > 0) {
+        Assert(n_indexes == 1); // Currently only support one type of block filter index
         size_t max_cache = std::min(total_cache * 5 / 100, MAX_FILTER_INDEX_CACHE);
         index_sizes.filter_index = max_cache / n_indexes;
         total_cache -= index_sizes.filter_index * n_indexes;