CompatHelper: bump compat for "DataStructures" to "0.18" (#186)

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: github-actions[bot]

Project.toml

@@ -17,7 +17,7 @@ Tables = "bd369af6-aec1-5ad0-b16a-f7cc5008161c"
 CategoricalArrays = "0.7"
 DataAPI = "1.1"
 DataFrames = "0.20, 0.21"
-DataStructures = "0.17.0"
+DataStructures = "0.17.0, 0.18"
 Distributions = "0.16, 0.17, 0.18, 0.19, 0.20, 0.21, 0.22, 0.23"
 ShiftedArrays = "1.0.0"
 StatsBase = "0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, 0.31, 0.32, 0.33"