Fixing command docs with new version of oclif readme

Author: dishantlangayan

README.md

@@ -120,7 +120,7 @@ USAGE
   $ sc help [COMMAND...] [-n]
 
 ARGUMENTS
-  COMMAND...  Command to show help for.
+  [COMMAND...]  Command to show help for.
 
 FLAGS
   -n, --nested-commands  Include all nested commands in the output.
@@ -764,7 +764,7 @@ USAGE
   $ sc plugins remove [PLUGIN...] [-h] [-v]
 
 ARGUMENTS
-  PLUGIN...  plugin to uninstall
+  [PLUGIN...]  plugin to uninstall
 
 FLAGS
   -h, --help     Show CLI help.
@@ -805,7 +805,7 @@ USAGE
   $ sc plugins uninstall [PLUGIN...] [-h] [-v]
 
 ARGUMENTS
-  PLUGIN...  plugin to uninstall
+  [PLUGIN...]  plugin to uninstall
 
 FLAGS
   -h, --help     Show CLI help.
@@ -833,7 +833,7 @@ USAGE
   $ sc plugins unlink [PLUGIN...] [-h] [-v]
 
 ARGUMENTS
-  PLUGIN...  plugin to uninstall
+  [PLUGIN...]  plugin to uninstall
 
 FLAGS
   -h, --help     Show CLI help.