update filename

Author: st--

src/KernelFunctions.jl

@@ -124,7 +124,7 @@ include("mokernels/lmm.jl")
 include("chainrules.jl")
 include("zygoterules.jl")
 
-include("test_utils.jl")
+include("TestUtils.jl")
 
 function __init__()
     @require Kronecker = "2c470bb0-bcc8-11e8-3dad-c9649493f05e" begin