fix tests

Author: sarahmish

.github/workflows/tests.yml

@@ -22,6 +22,7 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         python -m pip install invoke .[dev]
+        python -m pip uninstall xgboost --yes
     - name: Run lint checks
       run: invoke lint
 

tasks.py

@@ -2,6 +2,7 @@
 import os
 import shutil
 import stat
+import sys
 from pathlib import Path
 
 import tomli