added updates to llama cpp as a cron job

.github/workflows/update-llama-cpp.yml

@@ -0,0 +1,26 @@
+name: Update llama cpp nightly
+on:
+  schedule:
+    - cron: '0 0 * * *'
+  workflow_dispatch: {}
+
+permissions:
+  pull-requests: write
+  contents: read
+
+jobs:
+  update:
+    name: Update llama cpp
+    steps:
+      - uses: actions/checkout@v3
+        name: Checkout latest
+      - name: create branch
+        run: git checkout -b update-llama-cpp-$(date -I)
+      - name: update submodules
+        run: git submodule update --remote
+      - name: commit
+        run: git commit -am "updated llama.cpp"
+      - name: push
+        run: git push
+      - name: create pr
+        run: gh pr create --fill