Tabs demo - selected tab jumps back to first tab

[srambach]

Describe the problem
In the example for tabs linked to nav elements, after clicking to a tab other than the first, the view starts to jump back to the leftmost tab immediately after clicking another one.

This bug exists in V5 as well as V6.

Reported by @mshriver

[thatblindgeye]

We should try to make this example more functional to convey the intent, but if it is too messy/skirts too much on demo territory we should just update the example description to state that the example doesn't handle routing and it will be up to the consumer.

[mshriver]

https://github.com/ibutsu/ibutsu-server/pull/621/files#diff-c0da628a6378ea38af6d8d97b5dc617a202a9e673f8ab5ff6c28b57662b39de1

Here is an amateur's custom hook to handle an activeTab state and onTabSelect hook, but I dropped the href attribute for the Tab component to do so. If this is reasonable as a PF demo I can pull the commit out into the demo code?