Fix formatting

Signed-off-by: christopher-hakkaart <chris.hakkaart@seqera.io>

docs/install.md

@@ -71,7 +71,7 @@ Nextflow is distributed as a self-installing package, in order to make the insta
     Ensure the directory `$HOME/.local/bin/` is included in your `PATH` variable. If it is not, you can add it temporarily using `export PATH="$PATH:$HOME/.local/bin"`. To permanently add it to your `PATH` this command can be added to your shell configuration file, such as `~/.bashrc` or `~/.zshrc`. Alternatively, you could move the `nextflow` executable to a directory already in your `PATH`.
     :::
 
-    :::warning
+    :::{warning}
     Nextflow will update its executable during the self update process and it should not be placed in a directory with restricted permissions.
     :::