model doesn't require sourcing functions from utils - this was an error.

tests/testthat/example_project/model.R

@@ -6,9 +6,9 @@ library(miceadds)
 library(assertHE)
 
 # source local functions
-v_files <- list.files("./inst/example_project", full.names = T)
-v_files <- v_files[-grep(x = v_files, pattern = "example_script.R")]
-for(i in v_files)  source(i)
+#v_files <- list.files("./inst/example_project", full.names = T)
+#v_files <- v_files[-grep(x = v_files, pattern = "example_script.R")]
+#for(i in v_files)  source(i)
 
 # use default parameters from package
 params <- sicksickerPack::dummy_sickSickerModel_params