Support plugin probing in `inputs.chrony`

### Use Case

The chrony plugin should support probing to check if the chronyd service is reachable. Without this ability, the plugin continuously spams the logs with communication errors.

### Expected behavior

Implement `Probe() error` so that, if configured to do so, Telegraf will disable the plugin if an error is returned.

### Actual behavior

Currently this is not implemented.

### Additional info

_No response_

Start at the inputs.chrony plugin and inspect how its collection currently communicates with chronyd, then compare existing Telegraf plugins that implement probing. Add the requested Probe() error behavior so configured probing can disable the plugin when chronyd is unreachable, and verify the communication-error spam is prevented.

Written by the indexing model from the issue text.