5.0 prometheus exporter shows stats without a connection id

[matthewdarwin]

The Prometheus exporter shows stats without a connection id. These are useless and need to be suppressed. Missing connection ids appear in many the sections.

# TYPE nodeos_p2p_port gauge
nodeos_p2p_port{connid="a4a8ef5"} 33050
nodeos_p2p_port{connid="faa7038"} 60500
nodeos_p2p_port{connid="b2e92f7"} 44612
nodeos_p2p_port{connid="79a83fe"} 40418
nodeos_p2p_port{connid="1ed5718"} 35436
nodeos_p2p_port{connid="5550b49"} 35250
nodeos_p2p_port{connid="92e2810"} 32930
nodeos_p2p_port{connid="0621e81"} 44790
nodeos_p2p_port{connid="71b38d2"} 37328
nodeos_p2p_port{connid="9688002"} 35692
nodeos_p2p_port{connid=""} 0
nodeos_p2p_port{connid="690a93a"} 40128
nodeos_p2p_port{connid="4902897"} 50526
nodeos_p2p_port{connid="0585cab"} 33410
nodeos_p2p_port{connid="b8adc9e"} 35054
nodeos_p2p_port{connid="ca443ef"} 39416
nodeos_p2p_port{connid="cb1f404"} 45494
nodeos_p2p_port{connid="3775dd8"} 9876
nodeos_p2p_port{connid="78a3dab"} 43346
nodeos_p2p_port{connid="d00d383"} 9876
nodeos_p2p_port{connid="31cb243"} 53240
nodeos_p2p_port{connid="586c97a"} 9876
nodeos_p2p_port{connid="47a4e43"} 9876
nodeos_p2p_port{connid="6ab4fe0"} 9876