Adds retry logic for link checking

Improves link checking reliability by adding retry mechanisms for temporary failures.

Configures retry behavior with a maximum number of retries and a fallback delay.

Removes the hardcoded `aliveStatusCodes` to leverage the retry logic instead of explicitly allowing 429 status codes.

Author: edumserrano

.github/markdown-link-check-config-for-repo.json

@@ -38,5 +38,8 @@
       },
       "description": "Avoids 403s from GitHub docs"
     }
-  ]
+  ],
+  "retryOn429": true,
+  "retryCount": 3,
+  "fallbackRetryDelay": "3s"
 }

.github/markdown-link-check-config.json

@@ -20,6 +20,5 @@
       },
       "description": "Avoids 403s from GitHub docs"
     }
-  ],
-  "aliveStatusCodes": [429, 200]
+  ]
 }