[x] Change the _timevarname function to make it return an empty string instead of failing if there is no time variable in the dataset
[x] create test to handle 3 situations: time variable named time, time variable named something else but with standard_name=time, or a missing time variable
[x] Change the
_timevarnamefunction to make it return an empty string instead of failing if there is no time variable in the dataset[x] create test to handle 3 situations: time variable named
time, time variable named something else but withstandard_name=time, or a missing time variable