Co-Authored-By: John Newbery <email@example.com>
Currently we'll stall peers that send us an unknown INV type in a GETDATA message. Be a bit more friendly and just drop the invalid request.
Ditto for blocks-relay-only peers that send us a GETDATA for a transaction.
There's a test for the first part. The second is difficult to test in the functional test framework since we aren't able to make blocks-relay-only connections.
This is a backport of Core PR18808 [1/4]