add md link check action config

.github/mlc_config.json

@@ -0,0 +1,19 @@
+{
+    "aliveStatusCodes": [
+        429,
+        200
+    ],
+    "httpHeaders": [
+        {
+            "urls": [
+                "https://github.com/",
+                "https://guides.github.com/",
+                "https://help.github.com/",
+                "https://docs.github.com/"
+            ],
+            "headers": {
+                "Accept-Encoding": "zstd, br, gzip, deflate"
+            }
+        }
+    ]
+}