add user agent flag & slightly increase timeout

Author: TC-MO

.github/workflows/lychee.yml

@@ -46,7 +46,8 @@ jobs:
                         --max-retries 6
                         --verbose
                         --no-progress
-                        --timeout '45'
+                        --user-agent 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36'
+                        --timeout '60'
                         --accept '100..=103,200..=299,403..=403,429'
                         --format markdown
                         './build/**/*.html'