Remove duplication from reference.asciidoc

[sawell121]

Duplicated type entry, I left the entry at the top given that index + type are often mentioned in close proximity.

[elasticmachine]

Since this is a community submitted pull request, a Jenkins build has not been kicked off automatically. Can an Elastic organization member please verify the contents of this patch and then kick off a build manually?

[delvedor]

Hello! Thank you for contributing!
The reference.asciidoc is autogenerated from this script.
There is a duplicate entry because in the Elasticsearch's API you can pass that parameter as a query string or in the url.
Unless we figure out a way to exclude duplicated parameters, your change will be overwritten in the future.

[stale]

We understand that this might be important for you, but this issue has been automatically marked as stale because it has not had recent activity either from our end or yours.
It will be closed if no further activity occurs, please write a comment if you would like to keep this going.

Note: in the past months we have built a new client, that has just landed in master. If you want to open an issue or a pr for the legacy client, you should do that in https://github.com/elastic/elasticsearch-js-legacy

[delvedor]

I've opened #931 to track this bug :)