ci(dependabot): check for dependency updates

Schedule Dependabot to check for dependency updates every month. It is
important to keep on top of dependency updates to ensure patches are
regularly introduced.

Author: tomasbasham

.github/dependabot.yaml

@@ -0,0 +1,19 @@
+---
+version: 2
+updates:
+- package-ecosystem: github-actions
+  directory: /
+  schedule:
+    interval: weekly
+  commit-message:
+    prefix: ci(deps)
+- package-ecosystem: gomod
+  directory: /
+  schedule:
+    interval: monthly
+  commit-message:
+    prefix: chore(deps)
+  ignore:
+  - dependency-name: "*"
+    update-types:
+    - version-update:semver-major

.github/workflows/auto-merge.yaml

@@ -0,0 +1,12 @@
+---
+name: auto-merge
+on:
+  pull_request_target:
+permissions:
+  contents: write
+  pull-requests: write
+jobs:
+  auto-merge:
+    uses: tomasbasham/shared-workflows/.github/workflows/auto-merge.yaml@v1
+    with:
+      auto-merge-semver-minor: true