Release 0.22.4

# History

## 0.22.4

Install/update via the bootstrap script:

```shell
wget https://raw.githubusercontent.com/dokku/dokku/v0.22.4/bootstrap.sh
sudo DOKKU_TAG=v0.22.4 bash bootstrap.sh
```

### Bug Fixes

- #4274: @josegonzalez Use correct warning message for deprecated code

### New Features

- #4273: @josegonzalez Upgrade to golang 1.15

### Refactors

- #4275: @josegonzalez Add calls to verify app name in subcommands

### Documentation

- #4272: @josegonzalez Correct help output for ssh-keys command

### Tests

- #4276: @josegonzalez Upgrade version of plugn used in tests

README.md

@@ -99,8 +99,8 @@ Otherwise, you will need to import the keypair manually after installation using
 To install the latest stable release, run the following commands as a user who has access to `sudo`:
 
 ```shell
-wget https://raw.githubusercontent.com/dokku/dokku/v0.22.3/bootstrap.sh
-sudo DOKKU_TAG=v0.22.3 bash bootstrap.sh
+wget https://raw.githubusercontent.com/dokku/dokku/v0.22.4/bootstrap.sh
+sudo DOKKU_TAG=v0.22.4 bash bootstrap.sh
 ```
 
 You can then proceed to the ip address or domain name associated with your server to complete the web-based installation.