Automate Benchmarking - fixing issue. (#836)

## Summary
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this proposed code change. --->
Weekly runs were failing, fixed it. 
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## Details
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should be aware of?
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## Testing Done
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tested. --->

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- Hardware Type: <BLANK>
- [ ] run `make test` to ensure correctness
- [ ] run `make checkstyle` to ensure code style
- [ ] run `make test-convergence` to ensure convergence

---------

Co-authored-by: Manan Shah <[email protected]>
Co-authored-by: Vaibhav Jindal <[email protected]>

Author: 3 people

.github/workflows/benchmark.yml

@@ -39,24 +39,24 @@ jobs:
 
     steps:
       # Step: Decide the commit hash to use
+      # Step: Checkout full history so we can check out any commit
+      - name: Checkout full repo history
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 0  # Important: so we can checkout arbitrary commit
+          
       - name: Determine commit hash to checkout
         id: choose_commit
         run: |
-          if [ "${{ github.event.inputs.commit_hash }}" != "" ]; then
+          if [ "${{ github.event_name}}" == "workflow_dispatch" ] && [ "${{ github.event.inputs.commit_hash }}" != "main" ]; then
             echo "Using manual input commit: ${{ github.event.inputs.commit_hash }}"
             echo "hash=${{ github.event.inputs.commit_hash }}" >> $GITHUB_OUTPUT
           else
             echo "Using latest commit from main"
-            git fetch origin main
-            echo "hash=$(git rev-parse origin/main)" >> $GITHUB_OUTPUT
+            echo "hash=$(git rev-parse --short HEAD)" >> $GITHUB_OUTPUT
           fi
 
-      # Step: Checkout full history so we can check out any commit
-      - name: Checkout full repo history
-        uses: actions/checkout@v3
-        with:
-          fetch-depth: 0  # Important: so we can checkout arbitrary commit
-            # Step: Conditionally replace benchmark folder from main
+      # Step: Conditionally replace benchmark folder from main
       - name: Replace benchmark folder from main (manual only, commit ≠ main)
         if: ${{ github.event_name == 'workflow_dispatch' && github.event.inputs.commit_hash != 'main' }}
         run: |