FIX: Verify first word of _cmd in dependency check

Fixes #1235.

Author: effigies

fmriprep/cli/run.py

@@ -37,7 +37,7 @@ def check_deps(workflow):
         (node.interface.__class__.__name__, node.interface._cmd)
         for node in workflow._get_all_nodes()
         if (hasattr(node.interface, '_cmd') and
-            which(node.interface._cmd) is None))
+            which(node.interface._cmd.split()[0]) is None))
 
 
 def get_parser():