Switch from Dependabot to Renovate (#105)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: Leonard Brünings <leonard.bruenings@gradle.com>

.github/dependabot.yml

@@ -1,25 +0,0 @@
-# To get started with Dependabot version updates, you'll need to specify which
-# package ecosystems to update and where the package manifests are located.
-# Please see the documentation for all configuration options:
-# https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
-
-version: 2
-registries:
-  gradle-plugin-portal:
-    type: maven-repository
-    url: https://plugins.gradle.org/m2
-    username: dummy # Required by dependabot
-    password: dummy # Required by dependabot
-updates:
-  - package-ecosystem: "gradle"
-    directory: "/"
-    registries:
-      - gradle-plugin-portal
-    schedule:
-      interval: "weekly"
-    open-pull-requests-limit: 10
-  - package-ecosystem: "maven"
-    directory: "/"
-    schedule:
-      interval: "weekly"
-    open-pull-requests-limit: 10

.github/renovate.json5

@@ -0,0 +1,6 @@
+{
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "extends": [
+    "config:base"
+  ]
+}