renovate: Group non-major updates

The renovate PR spam we're seeing is too much.

Signed-off-by: Colin Walters <walters@verbum.org>

.github/renovate.json5

@@ -46,6 +46,20 @@
   // one commit.
   "rebaseWhen": "behind-base-branch",
 
+  "packageRules": [
+    {
+      "groupName": "all non-major dependencies",
+      "groupSlug": "all-minor-patch",
+      "matchPackagePatterns": [
+        "*"
+      ],
+      "matchUpdateTypes": [
+        "minor",
+        "patch"
+      ]
+    }
+  ],
+
   /*************************************************
    *** Repository-specific configuration options ***
    *************************************************/