feat: simplify flag parsing in apps plugin

Commands should be written such that they take arguments as is.

docs/appendices/0.21.0-migration-guide.md

@@ -7,3 +7,8 @@ The `tls` name is no longer a reserved app name, and can be used by applications
 ## Deprecations
 
 - `git#git_deploy_branch()` is deprecated in favor of `plugn trigger git-deploy-branch`.
+
+## Removals
+
+The `apps:destroy` command no longer takes a second argument `force`. Instead, this can be passed as the `--force` flag, either globally or as a flag to the command itself.
+

docs/deployment/application-management.md

@@ -103,6 +103,16 @@ dokku --force apps:destroy node-js-app
 Destroying node-js-app (including all add-ons)
 ```
 
+The `--force` flag can also be specified on the command vs globally:
+
+```shell
+dokku apps:destroy --force node-js-app
+```
+
+```
+Destroying node-js-app (including all add-ons)
+```
+
 Destroying an application will unlink all linked services and destroy any config related to the application. Note that linked services will retain their data for later use (or removal).
 
 ### Renaming a deployed app