update checkout to v4

.github/workflows/aggregate_signals.yml

@@ -1,15 +1,15 @@
-name: Run Python and Rust Scripts
+name: Aggregate Signals
 
 on:
   push:
 
 jobs:
-  run-scripts:
+  aggregate-signal:
     runs-on: ubuntu-latest
 
     steps:
     - name: Checkout code
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Set up Python
       uses: actions/setup-python@v4