Remove trailing spaces from bash completion command description (#1520)

completions.go

@@ -634,7 +634,7 @@ To load completions for every new session, execute once:
 	%[1]s completion bash > /usr/local/etc/bash_completion.d/%[1]s
 
 You will need to start a new shell for this setup to take effect.
-  `, c.Root().Name()),
+`, c.Root().Name()),
 		Args:                  NoArgs,
 		DisableFlagsInUseLine: true,
 		ValidArgsFunction:     NoFileCompletions,