Add anchors to buttons to easy navigation on Hyrax Downloads

[Mikejmnez]

Description

I briefly added buttons to better display the three options for downloading/installing hyrax to ease navigating the page, but so far they do not have anchor links attached to them that connect them to the various text options.

Visual Aid

For example, in the screenshot below, clicking "Docker Images" should take you to 1) Docker Images just below. Similarly for 2) Linux Binaries or 3) Source Code.

Page URL

https://www.opendap.org/hyrax-1-17/

[Mikejmnez]

@jgallagher59701 ready for review

• I am still having trouble with the padding of the anchors. But that is a separate issue. The buttons now have anchor links (and changed the color)