`https://datafusion.apache.org/blog/` routes to a directory listing

[paleolimbot]

When I click the "blog" link on the main DataFusion site (https://datafusion.apache.org/blog/) I get a directory listing and not the blog!

[kevinjqliu]

sorry about that! we're testing some changes in #180

reverting them so it should be back online soon

[kevinjqliu]

#180 was reverted in #182

we're back! https://datafusion.apache.org/blog/