Automerge safe dependencies (#288)

Simplify dependency management by automatically merging safe dependencies.

Automatically closes pull requests for plugin BOM updates if they pass
automated tests.  That avoids dependency updates in the plugin that
might make other maintenance more difficult.

Uses the GitHub Action defined in pull request:

* jenkins-infra/github-reusable-workflows#48

The pull request is associated with GitHub issue:

* jenkins-infra/github-reusable-workflows#35

Testing done:

* None.  Rely on testing done in other repositories

Author: MarkEWaite

.github/workflows/auto-merge-safe-deps.yml

@@ -0,0 +1,9 @@
+name: Automatically approve and merge safe dependency updates
+on:
+  - pull_request_target
+permissions:
+  contents: write
+  pull-requests: write
+jobs:
+  auto-merge-safe-deps:
+    uses: jenkins-infra/github-reusable-workflows/.github/workflows/auto-merge-safe-deps.yml@v1

.github/workflows/close-bom-if-passing.yml

@@ -0,0 +1,11 @@
+name: Close BOM update PR if passing
+on:
+  check_run:
+    types:
+      - completed
+permissions:
+  contents: read
+  pull-requests: write
+jobs:
+  close-bom-if-passing:
+    uses: jenkins-infra/github-reusable-workflows/.github/workflows/close-bom-if-passing.yml@v1