[refactor] Add CChainParams member to CConnman

This is done in preparation to the next commit, but has the nice
effect of removing one further data structure relying on the global
`Params()`.

src/test/fuzz/connman.cpp

@@ -36,6 +36,7 @@ FUZZ_TARGET(connman, .init = initialize_connman)
                      fuzzed_data_provider.ConsumeIntegral<uint64_t>(),
                      *g_setup->m_node.addrman,
                      *g_setup->m_node.netgroupman,
+                     Params(),
                      fuzzed_data_provider.ConsumeBool()};
     CNetAddr random_netaddr;
     CNode random_node = ConsumeNode(fuzzed_data_provider);