Clean test_utils notebook

no code changes, just cleanup

nbs/test_utils.ipynb

 %% Cell type:code id:411970cb tags:
 
 ``` python
 %load_ext autoreload
 %autoreload 2
 # default_exp test_utils
 ```
 
 %% Cell type:code id:48406581 tags:
 
 ``` python
 #export
 #hide
 import os
 
 def get_ci_variables(*varnames):
     """
     Gets ci variables from environment, can be set on gitlab in settings -> ci/cd -> variables
     """
     return {varname: os.environ.get(varname) for varname in varnames}
 ```
 
 %% Cell type:code id:8be91a62 tags:
 
 ``` python
 #ci
 #hide
 ci_test_credentials = get_ci_variables("TEST_CI_USERNAME", "TEST_CI_PASSWORD")
 assert ci_test_credentials['TEST_CI_USERNAME'] == "username"
 assert ci_test_credentials['TEST_CI_PASSWORD'] == "password"
 ```
 
-%% Output
 
-    False
-    False