Renovate: group Compose compiler and Kotlin version upgrades

.github/renovate.json

@@ -1,13 +0,0 @@
-{
-  "extends": [
-    "config:base"
-  ],
-  "schedule": ["every sunday"],
-  "packageRules": [
-    {
-      "managers": ["maven"],
-      "packageNames": ["com.google.guava:guava"],
-      "versionScheme": "docker"
-    }
-  ]
-}

.github/renovate.json5

@@ -0,0 +1,22 @@
+{
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "extends": [
+    "config:base"
+  ],
+  "schedule": ["every sunday"],
+  "packageRules": [
+    {
+      "managers": ["maven"],
+      "packageNames": ["com.google.guava:guava"],
+      "versionScheme": "docker"
+    },
+    {
+      // Compiler plugins are tightly coupled to Kotlin version
+      "groupName": "Kotlin",
+      "matchPackagePrefixes": [
+        "androidx.compose.compiler",
+        "org.jetbrains.kotlin",
+      ],
+    }
+  ]
+}