Fix `!draupnir ban` command example to not include a dash

A dash in the ban reason message makes Draupnir report this error:

> There was an unexpected argument provided for this command.
> draupnir ban <entity> <list> [...reason]
> Encountered unexpected keyword argument: all

docs/configuring-playbook-bot-draupnir.md

@@ -259,7 +259,7 @@ The simplest and most useful entity to target is `user`. Below are a few example
 To create rules, you run commands in the Management Room (**not** in the policy list room).
 
 - (ban a single user on a given homeserver): `!draupnir ban @charles:example.com my-bans Rude to others`
-- (ban all users on a given homeserver by using a [wildcard](https://the-draupnir-project.github.io/draupnir-documentation/moderator/managing-users#wildcards)): `!draupnir ban @*:example.org my-bans Spam server - all users are fake`
+- (ban all users on a given homeserver by using a [wildcard](https://the-draupnir-project.github.io/draupnir-documentation/moderator/managing-users#wildcards)): `!draupnir ban @*:example.org my-bans Spam server, all users are fake`
 
 As a result of running these commands, you may observe: