Fixup tests, add testing pipelines and small refactors

Signed-off-by: Ettore Di Giacinto <edigiacinto@suse.com>

backend/socket.go

@@ -2,6 +2,7 @@ package backend
 
 import "net"
 
+// Socket returns a fake TPM interface from a unix socket
 func Socket(f string) (*FakeTPM, error) {
 	conn, err := net.Dial("unix", f)
 	if err != nil {