fix: change benchmark tool from 'benchmarkjs' to 'customBiggerIsBetter'

The github-action-benchmark with tool: 'benchmarkjs' expects a different
format than what we're providing. The 'benchmarkjs' tool expects output
from the actual Benchmark.js library with specific fields.

Since we're providing custom JSON with 'name', 'unit', and 'value' fields,
we should use 'customBiggerIsBetter' tool instead (higher ops/sec is better).

This fixes the error:
'No benchmark result was found in bench-results.json'

The customBiggerIsBetter tool accepts our format:
[
  {
    "name": "...",
    "unit": "ops/sec",
    "value": 1234567
  }
]

Author: Isqanderm

.github/workflows/benchmark.yml

@@ -77,7 +77,7 @@ jobs:
         if: github.event_name == 'push' && github.ref == 'refs/heads/main'
         with:
           name: om-data-mapper Performance
-          tool: 'benchmarkjs'
+          tool: 'customBiggerIsBetter'
           output-file-path: bench-results.json
           github-token: ${{ secrets.GITHUB_TOKEN }}
           auto-push: true