Try bazel steward (#463)

.bazel-steward.yaml

@@ -0,0 +1,11 @@
+search-paths:
+  -
+    kinds: bazel
+    path-patterns:
+      - "bazel/BUILD.bazel"
+post-update-hooks:
+  - commands: "buildifier --lint=fix -r ."
+    files-to-commit:
+      - "bazel/BUILD.bazel"
+    run-for: pull-request
+    commit-message: "Apply buildifier"

.github/workflows/bazel-steward.yml

@@ -0,0 +1,15 @@
+name: Bazel Steward
+
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: '30 5 * * *' # runs every day at 5:30 am
+
+jobs:
+  bazel-steward:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      - uses: VirtusLab/bazel-steward@latest

.gitignore

@@ -24,7 +24,7 @@ build
 _build
 
 # bazel
-bazel-*
+bazel-*/
 
 # cmake related
 abseil-cpp