Network bridge metrics (#2818)

* add metrics (unused) to network bridge

* fix test compilation

* trigger metrics messages

* add some more metrics

* track sent and received notifications

* restore metrics import

* integrate into service

* Update node/network/bridge/src/lib.rs

Co-authored-by: Andronik Ordian <[email protected]>

* Update node/network/bridge/src/lib.rs

Co-authored-by: Andronik Ordian <[email protected]>

Co-authored-by: Andronik Ordian <[email protected]>