Add warning about token caching in gemini.html [no ci]

Author: stopsopa

pages/ai/gemini.html

@@ -33,6 +33,8 @@ <h2>General stuff</h2>
           <h2>Cli</h2>
           <script type="editor" data-lang="sh">
 
+            $ gemini
+            
             WARNING; 
               There is this thing called "token caching" https://geminicli.com/docs/cli/token-caching/
               Apparently it seems to be good idea to login to gemini cli using Gemini API Key to have that