bump Symutils

Author: shashi

Project.toml

@@ -50,7 +50,7 @@ Requires = "1.0"
 SafeTestsets = "0.0.1"
 SpecialFunctions = "0.7, 0.8, 0.9, 0.10"
 StaticArrays = "0.10, 0.11, 0.12"
-SymbolicUtils = "0.5"
+SymbolicUtils = "0.6"
 TreeViews = "0.3"
 UnPack = "0.1, 1.0"
 Unitful = "1.1"