Update src/go/rpk/pkg/cli/group/describe.go

Co-authored-by: Michele Cyran <michele@redpanda.com>

src/go/rpk/pkg/cli/group/describe.go

@@ -37,16 +37,16 @@ The --regex flag (-r) parses arguments as regular expressions
 and describes groups that match any of the expressions.
 `,
 		Example: `
-Describe groups foo and bar
+Describe groups foo and bar:
   rpk group describe foo bar
 
-Describe any group starting with f and any groups ending in r
+Describe any group starting with f and ending in r:
   rpk group describe -r '^f.*' '.*r$'
 
-Describe all groups
+Describe all groups:
   rpk group describe -r '*'
 
-Describe any one-character groups
+Describe any one-character group:
   rpk group describe -r .
 `,
 		Args: cobra.MinimumNArgs(1),