Fix git identity and ntfy URL in auto-update workflow

.gitea/workflows/auto-update.yaml

@@ -21,6 +21,11 @@ jobs:
           fetch-depth: 0
           ref: master
 
+      - name: Configure git identity
+        run: |
+          git config user.name "gitea-runner"
+          git config user.email "gitea-runner@neet.dev"
+
       - name: Update flake inputs
         run: nix flake update --commit-lock-file
 
@@ -39,4 +44,4 @@ jobs:
             -H "Priority: high" \
             -H "Tags: warning" \
             -d "Auto-update workflow failed. Check: ${{ gitea.server_url }}/${{ gitea.repository }}/actions/runs/${{ gitea.run_id }}" \
-            ntfy.neet.dev/nix-flake-updates
+            https://ntfy.neet.dev/nix-flake-updates