Fix ssh-agent plugin identities comment for using multiple identities.

plugins/ssh-agent/ssh-agent.plugin.zsh

@@ -9,7 +9,7 @@
 #   To load multiple identities use the identities style, For
 #   example:
 #
-#     zstyle :omz:plugins:ssh-agent id_rsa id_rsa2 id_github
+#     zstyle :omz:plugins:ssh-agent identities id_rsa id_rsa2 id_github
 #
 #   To set the maximum lifetime of the identities, use the
 #   lifetime style. The lifetime may be specified in seconds