[Feature Request] NavBar small changes

[kaimmej]

Is your feature request related to a problem? Please describe

We should provide a link direct to the docs site.
We should reformat the downloads button so that it stands out more from the background of the navbar.

Describe the solution you'd like to see

I suggest we change the header text in the big dropdown from "Getting Started with OpenSearch" to "Documentation Library". This should also be a live link to https://opensearch.org/docs/latest/

DownloadsButton:

Current

Change to look more like this.

Describe alternatives you've considered

No response

Additional context

No response