build: update .OwlBot.lock with new version of post-processor

.github/.OwlBot.lock.yaml

@@ -1,3 +1,3 @@
 docker:
-  digest: sha256:c3eae37a355402067b97cbeb6f5a7d2dd87aecfd064aeb2d2ea0bde40778cf68
+  digest: sha256:e301bd66e9c985734d806e1374a7a0dd89771a9d17007fa24935d7a3cba43739
   image: gcr.io/repo-automation-bots/owlbot-nodejs:latest

.github/generated-files-bot.yml

@@ -0,0 +1,13 @@
+generatedFiles:
+- path: '.kokoro/**'
+  message: '`.kokoro` files are templated and should be updated in [`synthtool`](https://github.com/googleapis/synthtool)'
+- path: '.github/CODEOWNERS'
+  message: 'CODEOWNERS should instead be modified via the `codeowner_team` property in .repo-metadata.json'
+- path: '.github/workflows/**'
+  message: '`.github/workflows` (GitHub Actions) should be updated in [`synthtool`](https://github.com/googleapis/synthtool)'
+- path: '.github/generated-files-bot.+(yml|yaml)'
+  message: '`.github/generated-files-bot.(yml|yaml)` should be updated in [`synthtool`](https://github.com/googleapis/synthtool)'
+- path: 'README.md'
+  message: '`README.md` is managed by [`synthtool`](https://github.com/googleapis/synthtool). However, a partials file can be used to update the README, e.g.: https://github.com/googleapis/nodejs-storage/blob/master/.readme-partials.yaml'
+- path: 'samples/README.md'
+  message: '`samples/README.md` is managed by [`synthtool`](https://github.com/googleapis/synthtool). However, a partials file can be used to update the README, e.g.: https://github.com/googleapis/nodejs-storage/blob/master/.readme-partials.yaml'