Avoid using union type for height

src/crop/aquacrop.jl

@@ -14,10 +14,10 @@ cropname(ct::AquaCropType) = ct.name
 
 mutable struct AquaCropState
     croptype::AquaCropType
-    height::Length{Float64}  # TODO: remove height field, supply from cropstate
+    height::Tlength  # TODO: remove height field, supply from cropstate
     cropstate::AquaCrop.AquaCropField
 
-    function AquaCropState(croptype::AquaCropType, height::Length{Float64}=0.0cm)
+    function AquaCropState(croptype::AquaCropType, height::Tlength=0.0cm)
         runtype = AquaCrop.TomlFileRun()
         parentdir = AquaCrop.test_toml_dir  # TODO: hardcoded croptype
         ac_cropfield, all_ok = AquaCrop.start_cropfield(; parentdir, runtype)