Update index.md

Status Job ID Name Coverage
  Test
failed #223
pages

00:01

 
Name Stage Failure
failed
pages Test
   7569919..e55641e  master     -> origin/master
Checking out e55641ec as master...
Skipping Git submodules setup
$ hugo
Building sites … ERROR 2018/07/06 15:43:20 posts/2018-07-05_Cage-the-Mastodon/index.md:16: unrecognized character in shortcode action: U+003C '<'. Note: Parameters with non-alphanumeric args must be quoted
ERROR 2018/07/06 15:43:20 Unable to locate template for shortcode "" in page "posts/2018-07-05_Cage-the-Mastodon/index.md"
Total in 893 ms
Error: Error building site: logged 2 error(s)
ERROR: Job failed: exit status 1