Update stg man page usage

jpgrayson · jpgrayson · commit 10ee58ef3ee1 · 2022-09-30T11:20:47.000-04:00
This usage matches the built-in usage from `stg -h`.
diff --git a/Documentation/stg.txt b/Documentation/stg.txt
@@ -10,7 +10,8 @@ SYNOPSIS
 --------
 [verse]
 'stg' [OPTIONS] <command> [...]
-'stg' [OPTIONS] \<--version|-h|--help>
+'stg' [OPTIONS] \<-h|--help>
+'stg' --version
 
 DESCRIPTION
 -----------
