FutureWarning: Deprecated downcasting behavior in pandas .fillna within babs.utils

[tien-tong]

Need to fix this

/gpfs/fs001/cbica/projects/executive_function/.local/share/mamba/envs/babs/lib/python3.11/site-packages/babs/utils.py:554: FutureWarning: Downcasting object dtype arrays on .fillna, .ffill, .bfill is deprecated and will change in a future version. Call result.infer_objects(copy=False) instead. To opt-in to the future behavior, set `pd.set_option('future.no_silent_downcasting', True)`
  updated_results_df['has_results'].fillna(False)
/gpfs/fs001/cbica/projects/executive_function/.local/share/mamba/envs/babs/lib/python3.11/site-packages/babs/utils.py:554: FutureWarning: Downcasting object dtype arrays on .fillna, .ffill, .bfill is deprecated and will change in a future version. Call result.infer_objects(copy=False) instead. To opt-in to the future behavior, set `pd.set_option('future.no_silent_downcasting', True)`
  updated_results_df['has_results'].fillna(False)
/gpfs/fs001/cbica/projects/executive_function/.local/share/mamba/envs/babs/lib/python3.11/site-packages/babs/utils.py:563: FutureWarning: Downcasting object dtype arrays on .fillna, .ffill, .bfill is deprecated and will change in a future version. Call result.infer_objects(copy=False) instead. To opt-in to the future behavior, set `pd.set_option('future.no_silent_downcasting', True)`
  bool(x) if pd.notna(x) else False for x in updated_results_df['has_results'].fillna(False)

[mattcieslak]

These are the kinds of issues I was hoping to fix with #302. There's really no need for pandas for BABS