I was messing around with min relay policies and found that under certain circumstances the mempool will accept things, then not relay to any peers.

Example made using wallet:
Transaction of size 6195, fee of 619 satoshis, minrelay of 100 satoshis per kvB. Mempool logic allows it:

```
        // No transactions are allowed below minRelayTxFee except from disconnected blocks
        if (!bypass_limits && nModifiedFees < ::minRelayTxFee.GetFee(nSize)) {
            return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "min relay fee not met", false, strprintf("%d < %d", nModifiedFees, ::minRelayTxFee.GetFee(nSize)));
        }
```
and lets it into mempool

but in net_processing.cpp:

```
                    if (filterrate && txinfo.feeRate.GetFeePerK() < filterrate) {
                        continue;
                    }
```
this gets hit because the computed feerate is insufficient(printing I added):
```
0.00000099 BTC/kB
```

I'm not super at arithmetic so I'm opening this up in case someone has an easy fix. 

let me also get a reproducible test failure with this...
"    Note: transactions that were re-added in the active chain will appear as-is in this array, and may thus have a positive confirmation count.\n"
            "  ],\n"
            "  \"lastblock\": \"lastblockhash\"     (string) The hash of the block (target_confirmations-1) from the best block on the main chain. This is typically used to feed back into listsinceblock the next time you call it. So you would generally use a target_confirmations of say 6, so you will be continually re-notified of transactions until they've reached 6 confirmations plus any new ones\n"
            "}\n"
                },
                RPCExamples{
                    HelpExampleCli("listsinceblock", "")
            + HelpExampleCli("listsinceblock", "\"000000000000000bacf66f7497b7dc45ef753ee9a7d38571037cdb1a57f663ad\" 6")
            + HelpExampleRpc("listsinceblock", "\"000000000000000bacf66f7497b7dc45ef753ee9a7d38571037cdb1a57f663ad\", 6")
                },
            }.Check(request);
    
    
    pwallet->BlockUntilSyncedToCurrentChain();
    auto locked_chain = pwallet->chain().lock();
    LOCK(pwallet->cs_wallet);
    
    Optional<int> height = MakeOptional(false, int()); 
    Optional<int> altheight; 
    int target_confirms = 1;
    isminefilter filter = ISMINE_SPENDABLE;
    uint256 blockId;
    if (!request.params[0].isNull() && !request.params[0].get_str().empty()) {
        blockId = ParseHashV(request.params[0], "blockhash");
        height = locked_chain->findFork(blockId, &altheight);
        if (!height) {
            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
        }
    }
    if (!request.params[1].isNull()) {