Update Graphs requirement to 1.13.3 in /docs (#112)

Updates the requirements on [Graphs](https://github.com/JuliaGraphs/Graphs.jl) to permit the latest version.
- [Release notes](https://github.com/JuliaGraphs/Graphs.jl/releases)
- [Commits](JuliaGraphs/Graphs.jl@v0.10.0...v1.13.3)

---
updated-dependencies:
- dependency-name: Graphs
  dependency-version: 1.13.3
  dependency-type: direct:production
...

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docs/Project.toml

@@ -8,4 +8,5 @@ MetaGraphs = "626554b9-1ddb-594c-aa3c-2596fe9399a5"
 MetaGraphsNext = "fa8bd995-216d-47f1-8a91-f3b68fbeb377"
 
 [compat]
-Documenter = "1"
+Documenter = "1"
+Graphs = "1.13.3"