Remove extra space to fix broken doc versioned plugin reference build

[dedemorton]

The extra space in the link was causing problems with the versioned plugin reference build because the cleanup part of the script was unable to make the necessary replacement: https://github.com/elastic/docs-tools/blob/master/versioned_plugins.rb#L224

[robbavey]

Would you mind fixing up the changelog entry? We are trying to introduce some consistency into how we format our changelog entries

[robbavey]

Would you mind changing this to use the format described in the logstash plugin contribution guidelines for writing changelogs?

[dedemorton]

@robbavey Is this what you had in mind? 29ff0bc

[robbavey]

@dedemorton I think that should be ok - the general guidelines are to start with 'Fixed/Added/Changed' etc, but I don't necessarily think that prepending an entry with Docs: is an issue

[dedemorton]

@robbavey I'd be happy to reevaluate, but I think flagging the issue as doc-related helps people skip over changes that are mostly superficial. We could use [Docs] instead of Docs: to make it look more consistent in the changelog? I don't have a strong preference, but I do think it's worth flagging doc-only changes.