Add Terraform/HCL syntax highlighting

Author: spikeheap

docusaurus.config.js

@@ -168,6 +168,7 @@ const config = {
         copyright: `Copyright © ${new Date().getFullYear()} London Borough of Hackney Council. The data published here is free to re-use under the <a href="https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/">Open Government Licence</a>.`,
       },
       prism: {
+        additionalLanguages: ['hcl'],
         theme: prismThemes.github,
         darkTheme: prismThemes.dracula,
       },