fix(deps): use managerFilePatterns instead of deprecated fileMatch

Renovate renamed fileMatch to managerFilePatterns. Using the old name
triggers an automatic migration PR that strips all JSON5 comments.
Switch to the new option name with regex syntax to prevent that.

Author: kzndotsh

.github/renovate.json5

@@ -210,9 +210,9 @@
   // Default pattern only matches compose*.y{a,}ml and docker-compose*.y{a,}ml
   // Exclude infra/sh/ (Ansible YAML, not compose)
   "docker-compose": {
-    fileMatch: [
-      "(^|/)infra/(?!sh/).+\\.ya?ml$",
-      "(^|/)infra/[^/]+\\.ya?ml$",
+    managerFilePatterns: [
+      "/infra/(?!sh/).+\\.ya?ml$/",
+      "/infra/[^/]+\\.ya?ml$/",
     ],
   },
   // Use platform-native automerge (GitHub/GitLab built-in automerge)