Update helm deps weekly (#510)

As title. This modification should only apply the minor+patch updates for the helm deps of this chart on a weekly basis. Major updates should still come in with the daily renovate runs.

Automerge is included but won't work as the bot cannot self-approve it's PRs and does not have merge permissions yet.
The only way this might work if we allow the bot to push to a branch only and merge without opening a PR.

Reviewed-on: https://gitea.com/gitea/helm-chart/pulls/510
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: pat-s <patrick.schratz@gmail.com>
Co-committed-by: pat-s <patrick.schratz@gmail.com>

renovate.json5

@@ -1,4 +1,13 @@
 {
-  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
-  "extends": ["gitea>gitea/renovate-config"],
+  $schema: "https://docs.renovatebot.com/renovate-schema.json",
+  extends: ["gitea>gitea/renovate-config"],
+  packageRules: [
+    {
+      description: "Automerge minor + patch dependency updates weekly",
+      matchManagers: ["helm"],
+      matchUpdateTypes: ["minor", "patch", "digest"],
+      automerge: true,
+      schedule: ["weekly"]
+    },
+  ],
 }