Update Renovate config

.reuse/dep5

@@ -10,3 +10,7 @@ License: MIT
 Files: Pipfile.lock migrations/*
 Copyright: WTF Kooperative eG <https://wtf-eg.de/>
 License: AGPL-3.0-or-later
+
+Files: renovate.json
+Copyright: WTF Kooperative eG <https://wtf-eg.de/>
+License: AGPL-3.0-or-later

renovate.json

@@ -1,3 +1,18 @@
 {
-  "$schema": "https://docs.renovatebot.com/renovate-schema.json"
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "extends": [
+    "config:best-practices",
+    ":disableDependencyDashboard",
+    ":maintainLockFilesMonthly",
+    ":pinVersions",
+    ":separateMultipleMajorReleases"
+  ],
+  "packageRules": [
+    {
+      "matchDepNames": ["python"],
+      "groupName": "Python",
+      "separateMinorPatch": true,
+      "separateMultipleMinor": true
+    }
+  ]
 }