ci: add daily check for core update (#955)

* ci: add daily check for core update

* update

* update

.github/workflows/update-core.yaml

@@ -0,0 +1,42 @@
+name: Update Core to Latest Commit
+
+on:
+  schedule:
+    - cron: '40 1 * * *'
+  workflow_dispatch:
+
+jobs:
+  update-pomerium-core:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@0ad4b8fadaa221de15dcec353f45205ec38ea70b
+      - name: Setup Go
+        uses: actions/setup-go@0c52d547c9bc32b1aa3301fd7a9cb496313a4491
+        with:
+          go-version: 1.22.x
+      - name: Update Core
+        run: |
+          go get -u github.com/pomerium/pomerium@main
+          go mod tidy
+      - name: Check for changes
+        id: git-diff
+        run: |
+          git config --global user.email "apparitor@users.noreply.github.com"
+          git config --global user.name "GitHub Actions"
+          git add go.mod go.sum
+          git diff --cached --exit-code || echo "changed=true" >> $GITHUB_OUTPUT
+
+      - name: Create Pull Request
+        if: ${{ steps.git-diff.outputs.changed }} == 'true'
+        uses: peter-evans/create-pull-request@6d6857d36972b65feb161a90e484f2984215f83e
+        with:
+          author: GitHub Actions <apparitor@users.noreply.github.com>
+          body: "This PR updates the Pomerium Core to the latest commit in main"
+          branch-suffix: random
+          branch: ci/update-core
+          commit-message: "ci: update core to latest commit in main"
+          delete-branch: true
+          labels: ci
+          title: "ci: update core to latest commit in main"
+          token: ${{ secrets.APPARITOR_GITHUB_TOKEN }}