fix: Missing logger (#3624)

Closes #3616.

Author: effigies

fmriprep/workflows/bold/base.py

@@ -714,7 +714,9 @@ def init_bold_wf(
                 template = ref_.space
                 density = ref_.spec.get('density') or ref_.spec.get('den') or None
                 if density is None:
-                    config.loggers.warning(f'Cannot resample {ref_} without density specified.')
+                    config.loggers.workflow.warning(
+                        f'Cannot resample {ref_} without density specified.'
+                    )
                     continue
 
                 resample_surfaces_wf = init_resample_surfaces_wf(