chore(ci): increase bench timeout to 6h

https://docs.github.com/en/actions/administering-github-actions/usage-limits-billing-and-administration#usage-limits

6h = current gh action limit.

.github/workflows/benchmark-master-push.yml

@@ -31,7 +31,7 @@ jobs:
       - name: Run benchmark
         run: |
           go test -benchmem -bench=. ./... -run=^$ \
-          -cpu 1,2 -timeout 50m | tee benchmarks.txt
+          -cpu 1,2 -timeout 300m | tee benchmarks.txt
 
       - name: Download previous benchmark data
         uses: actions/cache@v4