Node registration to Trident CSI controller fails by communication error

• the Trident node container fails to register its host node to the Trident CSI controller with the following message in its log:

level=warning msg="Could not update Trident controller with node registration, will retry." error="could not log into the Trident CSI Controller: error communicating with Trident CSI Controller; Put \"https://<TRIDENT_CSI>:34571/trident/v1/node/<WORKER_NODE>": dial tcp <TRIDENT_CSI>:34571: connect: connection refused" increment=10.34424336s requestID=<UUID> requestSource=Internal

• The Trident driver-registrar logs for the contain return an error with connecting to the unix socket:

    W0814 02:11:11.445999   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:11:21.446191   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:11:31.446114   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:11:41.446161   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:11:51.445607   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:12:01.445543   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:12:11.445383   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:12:21.445937   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:12:31.445422   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:12:41.445792   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock
    W0814 02:12:51.445988   22234 connection.go:173] Still connecting to unix:///plugin/csi.sock  

• the trident-controller container accepts REST API calls from other clients