docs: pass on sub-command help

cli/app/upgrade.go

@@ -34,15 +34,10 @@ var appUpgradeCommand = cli.Command{
 	},
 	Before: internal.SubCommandBefore,
 	Description: `
-Upgrade an app. You can use it to choose and roll out a new upgrade to a
-deployed app.
-
-You may pass "--force/-f" to upgrade to the same version again. This can be
-useful if the container runtime has gotten into a weird state.
+Upgrade an app.
 
 This action could be destructive, please ensure you have a copy of your app
-data beforehand.
-`,
+data beforehand.`,
 	BashComplete: autocomplete.AppNameComplete,
 	Action: func(c *cli.Context) error {
 		app := internal.ValidateApp(c)