CompatHelper: bump compat for CairoMakie to 0.15 for package docs, (keep existing compat) (#481)

* CompatHelper: bump compat for CairoMakie to 0.15 for package docs, (keep existing compat)

* Update docs/Project.toml

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

Author: 3 people

docs/Project.toml

@@ -10,7 +10,7 @@ MLJDecisionTreeInterface = "c6f25543-311c-4c74-83dc-3ea6d1015661"
 StatsPlots = "f3b207a7-027a-5e70-b257-86293d7955fd"
 
 [compat]
-CairoMakie = "0.6 - 0.13.0, 0.13.2 - 0.13"
+CairoMakie = "0.6 - 0.13.0, 0.13.2 - 0.15"
 CategoricalArrays = "0.8, 0.9, 0.10"
 DataFrames = "0.22, 1"
 Documenter = "0.26, 0.27, 1"