Fix broken link to run_app_with_gemini_key.md in examples READMEs#854

omarfarouk228 wants to merge 4 commits intoflutter:mainflutter/genui:mainfrom

omarfarouk228:fix/broken-link-gemini-key-docsomarfarouk228/genui:fix/broken-link-gemini-key-docsCopy head branch name to clipboard