* Only show the top 40 blog tags
In https://github.com/pulumi/pulumi-hugo/pull/215, I had suggested
that instead of physically deleting tags we didn't want to show, we
compute it algorithmically, by only showing the "Top N" tags. This
commit introduces said functionality.
This has a few advantages:
* Preserves old metadata (the authors added the tags because they
felt they were meaningful and captured information about the posts).
* Enables us to surface those tags differently in the future (who
knows, maybe someday we'll want to run a "spinnaker" campaign).
* Notably, also keeps the tag index pages, which Google has indexed.
* Enables us to add a "View More ..." link at the bottom of the
page if folks want to see the entire list.
* Perhaps most importantly, protects against future bloat. For
example, since this tag cleanup happened, we have added top-level
tags for "aliases", "app-runner", "iam", "open-source", and
"refactoring", each of which has only a single post.
I chose 40 as the N in Top N, because that's how many we show today.
I could see an argument for filtering this based on post count
instead (e.g., only those with >3 posts).
* Add back some tags
Now that we filter out unpopular tags, we can add back some of the
ones previously removed.
