build(deps): update BenchmarkTools requirement to 1.8.0 in /benchmark

Updates the requirements on [BenchmarkTools](https://github.com/JuliaCI/BenchmarkTools.jl) to permit the latest version.
- [Release notes](https://github.com/JuliaCI/BenchmarkTools.jl/releases)
- [Commits](JuliaCI/BenchmarkTools.jl@v0.0.1...v1.8.0)

---
updated-dependencies:
- dependency-name: BenchmarkTools
  dependency-version: 1.8.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

benchmark/Project.toml

@@ -14,3 +14,6 @@ SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 SparseConnectivityTracer = "9f842d2f-2579-4b1d-911e-f412cf18a3f5"
 SparseMatrixColorings = "0a514795-09f3-496d-8182-132a7b665d35"
 UnoSolver = "1baa60ac-02f7-4b39-a7a8-2f4f58486b05"
+
+[compat]
+BenchmarkTools = "1.8.0"