Add Renovate regex manager for Chainguard MinIO container digest

Configure a custom regex manager so Renovate can detect and update the
cgr.dev/chainguard/minio digest pinned in S3Container.java.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: mosabua

.github/renovate.json

@@ -6,5 +6,19 @@
   "pinDigests": true,
   "prConcurrentLimit": 0,
   "branchConcurrentLimit": 0,
-  "prHourlyLimit": 0
+  "prHourlyLimit": 0,
+  "customManagers": [
+    {
+      "customType": "regex",
+      "managerFilePatterns": [
+        "trino-aws-proxy/src/test/java/io/trino/aws/proxy/server/testing/containers/S3Container.java"
+      ],
+      "matchStrings": [
+        "cgr\\.dev/chainguard/minio@(?<currentDigest>sha256:[a-f0-9]+)"
+      ],
+      "depNameTemplate": "cgr.dev/chainguard/minio",
+      "datasourceTemplate": "docker",
+      "currentValueTemplate": "latest"
+    }
+  ]
 }