Configure auto-approve, mergify and renovate bots (#171)

.github/workflows/auto-approve.yml

@@ -0,0 +1,13 @@
+name: Auto approve
+
+on:
+  pull_request_target
+
+jobs:
+  auto-approve:
+    runs-on: ubuntu-20.04
+    steps:
+      - uses: hmarr/[email protected]
+        if: github.actor == 'scala-steward' || github.actor == 'renovate[bot]'
+        with:
+          github-token: "${{ secrets.AUTO_APPROVE_GITHUB_ACCESS_TOKEN }}"

.mergify.yml

@@ -0,0 +1,8 @@
+pull_request_rules:
+  - name: Merge Scala Steward's PRs
+    conditions:
+      - "author=scala-steward"
+      - "status-success=ci"
+    actions:
+      merge:
+        method: squash

renovate.json

@@ -1,6 +1,12 @@
 {
-  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
-  "extends": [
-    "config:base"
+  "automerge": true,
+  "rebaseWhen": "conflicted",
+  "packageRules": [
+    {
+      "matchManagers": [
+        "sbt"
+      ],
+      "enabled": false
+    }
   ]
 }