CompatHelper: bump compat for Trixi to 0.13 for package docs, (keep existing compat) (#70)

Co-authored-by: CompatHelper Julia <[email protected]>

Author: github-actions[bot]

docs/Project.toml

@@ -12,5 +12,5 @@ CairoMakie = "0.13"
 Changelog = "1.1"
 Documenter = "1.3"
 OrdinaryDiffEqLowStorageRK = "1.3"
-Trixi = "0.12"
+Trixi = "0.12, 0.13"
 TrixiShallowWater = "0.2"