Update CONTRIBUTING.md to use latest cuda env (#15467)

clean commit of #15401

Authors:
  - Ray Bell (https://github.com/raybellwaves)
  - Bradley Dice (https://github.com/bdice)

Approvers:
  - Nghia Truong (https://github.com/ttnghia)
  - Bradley Dice (https://github.com/bdice)

URL: #15467

CONTRIBUTING.md

@@ -105,7 +105,7 @@ Instructions for a minimal build environment without conda are included below.
 # create the conda environment (assuming in base `cudf` directory)
 # note: RAPIDS currently doesn't support `channel_priority: strict`;
 # use `channel_priority: flexible` instead
-conda env create --name cudf_dev --file conda/environments/all_cuda-118_arch-x86_64.yaml
+conda env create --name cudf_dev --file conda/environments/all_cuda-122_arch-x86_64.yaml
 # activate the environment
 conda activate cudf_dev
 ```