Fix Colab and Notebook checks for `diffusers-cli env` (#8408)
* chore: Update is_google_colab check to use environment variable
* Check Colab with all possible COLAB_* env variables
* Remove unnecessary word
* Make `_is_google_colab` more inclusive
* Revert "Make `_is_google_colab` more inclusive"
This reverts commit 6406db21ac46139c20ccae20ccb44877eec87ba7.
* Make `_is_google_colab` more inclusive.
* chore: Update import_utils.py with notebook check improvement
* Refactor import_utils.py to improve notebook detection for VS Code's notebook
* chore: Remove `is_notebook()` function and related code
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Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>
