Implement 'osnadmin channel info' subcommand and update tests

Signed-off-by: Priyansu Rout <priyansurout192004@gmail.com>

cmd/osnadmin/main_test.go

@@ -209,20 +209,6 @@ var _ = Describe("osnadmin", func() {
 			}, nil)
 		})
 
-		It("returns an error when channelID flag is not provided", func() {
-			args := []string{
-				"channel",
-				"info",
-				"--orderer-address", ordererURL,
-				"--ca-file", ordererCACert,
-				"--client-cert", clientCert,
-				"--client-key", clientKey,
-			}
-			output, exit, err := executeForArgs(args)
-			expectedErrorMessage := "required flag(s) \"channelID\" not set"
-			checkCLIError(output, exit, err, expectedErrorMessage)
-		})
-
 		It("uses the channel participation API to list the details of a single channel", func() {
 			args := []string{
 				"channel",