[Test] Rename const transport test

test/const_solute.mini.in

@@ -6,7 +6,9 @@ _evaluation = const
 _model = transport
 _quantity = solute
 _tol = 1E-8
-__name = const_solute
+_diff = conv, diff            | expand diff
+_param = sand, silt, layered  | expand param
+__name = const_solute_{_diff}_{_param}
 
 [simulation]
 mode = richards+transport
@@ -34,8 +36,8 @@ time.startTimestep = 1E4
 numerics.FEorder = 1
 
 [transport]
-output.fileName = const_solute | unique
-output.outputPath = const_solute | unique
+output.fileName = {__name}
+output.outputPath = {__name}
 output.vertexData = false
 output.policy = endOfRichardsStep