Tags do not get aggregated

[EyalIsr]

I'm not sure what's the reason for this, but "Popular tags" on the 5.x.net-core displays empty list.
I'm suspecting it just wasn't aggregated on the search query, but I'm not sure.
BYW, demo app DOES showing the tags.

[russcam]

@EyalIsr Your're correct, it's not included in the walkthrough or the final code. The demo app is running the 5.x-codecomplete-netcore-modifications branch implementation of SearchController which includes the aggregations, so you can take them from there.

Happy to accept a PR for bringing the changes and a walkthrough into the 5.x-[codecomplete]-netcore branches 😄