remove large repo from demo config

Author: brendan-kellam

demo-site-config.json

@@ -435,7 +435,6 @@
                 "freqtrade/freqtrade",
                 "bayandin/awesome-awesomeness",
                 "KRTirtho/spotube",
-                "doocs/leetcode",
                 "geekcomputers/Python",
                 "Pythagora-io/gpt-pilot",
                 "reworkd/AgentGPT",