ci: Enhance benchmarking traceability for bench comments (#850)

- Enhanced the benchmark output's system information in `merge-tests.yml` to include CPU model and total RAM besides GPU name.

.github/workflows/merge-tests.yml

@@ -115,8 +115,17 @@ jobs:
       - name: copy the benchmark template and prepare it with data
         run: |
           cp .github/tables.toml .
-          sed -i -Ee 's/^"""$//g' tables.toml
-          echo "$(nvidia-smi --query-gpu=gpu_name --format=csv|tail -n1)\n\"\"\"" >> tables.toml
+          # Get GPU name
+          GPU_NAME=$(nvidia-smi --query-gpu=gpu_name --format=csv,noheader,nounits | tail -n1)
+          # Get CPU model
+          CPU_MODEL=$(grep '^model name' /proc/cpuinfo | head -1 | awk -F ': ' '{ print $2 }')
+          # Get total RAM
+          TOTAL_RAM=$(grep MemTotal /proc/meminfo | awk '{print $2 $3}')
+          
+          # Use conditionals to ensure that only non-empty variables are inserted
+          [[ ! -z "$GPU_NAME" ]] && sed -i "/^\"\"\"$/i $GPU_NAME" tables.toml
+          [[ ! -z "$CPU_MODEL" ]] && sed -i "/^\"\"\"$/i $CPU_MODEL" tables.toml
+          [[ ! -z "$TOTAL_RAM" ]] && sed -i "/^\"\"\"$/i $TOTAL_RAM" tables.toml          
         working-directory: ${{ github.workspace }}
       # Create a `criterion-table` and write in commit comment
       - name: Run `criterion-table`