Update NNlib compat

Author: pxl-th

Project.toml

@@ -38,7 +38,7 @@ ChainRulesCore = "1.12"
 Functors = "0.3, 0.4"
 MLUtils = "0.2, 0.3.1, 0.4"
 MacroTools = "0.5"
-NNlib = "0.8.15"
+NNlib = "0.8.19"
 NNlibCUDA = "0.2.6"
 OneHotArrays = "0.1, 0.2"
 Optimisers = "0.2.12"