💽 fix: Exclude index page / from static cache settings (#7382)

* Disable default static caching for app's index page

* Update index.html related environment variables in `.env.example`

* Fix linting

* Update index.spec.js

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Co-authored-by: Danny Avila <danacordially@gmail.com>

api/server/utils/staticCache.js

@@ -14,6 +14,7 @@ const staticCache = (staticPath) =>
         res.setHeader('Cache-Control', `public, max-age=${maxAge}, s-maxage=${sMaxAge}`);
       }
     },
+    index: false,
   });
 
 module.exports = staticCache;