CompatHelper: add new compat entry for Libtask at version 0.6 for package test, (keep existing compat)

Author: CompatHelper Julia

test/Project.toml

@@ -43,6 +43,7 @@ DynamicPPL = "0.17.2"
 FiniteDifferences = "0.10.8, 0.11, 0.12"
 ForwardDiff = "0.10.12"
 GalacticOptim = "0.4, 1, 2"
+Libtask = "0.6"
 MCMCChains = "5"
 Memoization = "0.1.4"
 NamedArrays = "0.9.4"