experiment: add codspeed using vitest

Author: erikwrede

.github/workflows/codspeed.yml

@@ -21,5 +21,5 @@ jobs:
       - name: Run benchmarks
         uses: CodSpeedHQ/action@v3
         with:
-          run: node --loader ts-node/esm resources/benchmark-tinybench.ts
+          run: npm exec vitest bench
           token: ${{ secrets.CODSPEED_TOKEN }}