Use new renovate confix

Author: DRSchlaubi

renovate.json

@@ -6,10 +6,22 @@
       "customType": "regex",
       "description": "Update curl Version",
       "fileMatch": ["Dockerfile"],
-      "matchStrings": ["curl-(?<currentValue>\\d+\\.\\d+\\.\\d+)\\.tar\\.gz"],
-      "datasourceTemplate": "github-releases",
+      "matchStrings": ["(?<currentValue>curl-\\d+\\.\\d+\\.\\d+)"],
+      "datasourceTemplate": "custom.curl",
       "depNameTemplate": "curl/curl",
-      "versioningTemplate": "regex:^(?:curl-)?(?<major>\\d+)[_.](?<minor>\\d+)[_.](?<patch>\\d+)$"
+      "versioningTemplate": "regex:curl-(?<major>\\d+)\\.(?<minor>\\d+)\\.(?<patch>\\d+)"
+    }
+  ],
+  "customDatasources": {
+    "curl": {
+      "defaultRegistryUrlTemplate": "https://curl.se/download.html",
+      "format": "html"
+    }
+  },
+  "packageRules": [
+    {
+      "matchDatasources": ["custom.curl"],
+      "extractVersion": "/curl-(?<version>.+)\\.tar\\.gz$"
     }
   ]
 }