Merge branch 'dm/update-index-doc-fix' into maint-2.45

Doc fix.

* dm/update-index-doc-fix:
  documentation: git-update-index: add --show-index-version to synopsis

Author: gitster

Documentation/git-update-index.txt

@@ -25,6 +25,7 @@ SYNOPSIS
 	     [--really-refresh] [--unresolve] [--again | -g]
 	     [--info-only] [--index-info]
 	     [-z] [--stdin] [--index-version <n>]
+	     [--show-index-version]
 	     [--verbose]
 	     [--] [<file>...]