The compression extension won’t help you much. GDevelop code should be minified by default in the latest versions of GDevelop. I would recommend trying out cloudflare pages or netlify as they are notoriously fast professional and extremely affordable (mostly free) static sites hosts. Netlify also supports minifying code for you automatically and invisibly. Generally, I would recommend putting cloudflare in front of your site, as it allows to serve your game from servers that are geographically near your users so that latency due to distance from the server is not an issue.
Otherwise, as an additional optimisation, you can look into adding a service worker to your site. This won’t make the first load faster, but it will allow you to specify caching rules for your site files to be stored locally instead of needing to refetch them from the server everytime, leading to faster subsequent loads.