PHP 8.2: explicitly declare CompositeCommand::$longdesc to fix deprecation warning by rodrigoprimo · Pull Request #5707 · wp-cli/wp-cli

@rodrigoprimo

This commit fixes the following deprecation warnings when running `wp
--info` with PHP 8.2 RC6:

```
Deprecated: Creation of dynamic property WP_CLI\Dispatcher\CompositeCommand::$longdesc is deprecated in phar:///usr/local/bin/wp/vendor/wp-cli/wp-cli/php/WP_CLI/Dispatcher/CompositeCommand.php on line 38
Deprecated: Creation of dynamic property WP_CLI\Dispatcher\Subcommand::$longdesc is deprecated in phar:///usr/local/bin/wp/vendor/wp-cli/wp-cli/php/WP_CLI/Dispatcher/CompositeCommand.php on line 38
Deprecated: Creation of dynamic property WP_CLI\Dispatcher\CommandNamespace::$longdesc is deprecated in phar:///usr/local/bin/wp/vendor/wp-cli/wp-cli/php/WP_CLI/Dispatcher/CompositeCommand.php on line 38
```

Dynamic properties are deprecated in PHP 8.2. The solution was to simply
declare CompositeCommand::$longdesc before it is used.