Please 'trim' server name

[thepurpleblob]

If you accidentally add a space at the end of the server name in the Redis config, Moodle doesn't care. It works fine. I assume it must trim the hostname.

However, this breaks moodle-tool_redis with a DNS resolution error.

Please consider adding a trim() to be consistent.

[abias]

Thank you @thepurpleblob for this issue.
I agree that there is room for improvement. And i think that this will be fixed by #7 as soon as that PR is improved and merged.
Until then, I will leave the issue here open.

Cheers,
Alex