Use Conda XGBoost (#17959)

Switch to Conda XGBoost in Conda-based test of third-party dependencies.

Authors:
  - https://github.com/jakirkham
  - GALI PREM SAGAR (https://github.com/galipremsagar)

Approvers:
  - Matthew Murray (https://github.com/Matt711)
  - GALI PREM SAGAR (https://github.com/galipremsagar)
  - Jake Awe (https://github.com/AyodeAwe)

URL: #17959

python/cudf/cudf_pandas_tests/third_party_integration_tests/dependencies.yaml

@@ -242,8 +242,7 @@ dependencies:
           - scipy
           - scikit-learn
           - pip
-          - pip:
-            - xgboost>=2.0.1
+          - xgboost>=2.0.1
   test_cuml:
     common:
       - output_types: conda