chore: use built-in github-actions manager for README instead of custom regex

Author: erezrokah

.github/renovate.json5

@@ -52,15 +52,8 @@
       datasourceTemplate: "github-releases",
       extractVersionTemplate: "^cli-(?<version>.+)$",
     },
-    {
-      // GitHub Actions in README.md (e.g. actions/checkout@v4, aws-actions/configure-aws-credentials@v4)
-      // Excludes cloudquery/setup-cloudquery which is managed by release-please
-      customType: "regex",
-      fileMatch: ["^README\\.md$"],
-      matchStrings: [
-        "uses:\\s+(?<depName>(?!cloudquery/setup-cloudquery)[\\w-]+/[\\w-]+)@(?<currentValue>[^\\s#]+)",
-      ],
-      datasourceTemplate: "github-tags",
-    },
   ],
+  "github-actions": {
+    fileMatch: ["^README\\.md$"],
+  },
 }