Revert "fix(controller): use /bin/sh as entrypoint for run"

This reverts commit 92cb26a054afff117e4c56f434cc00093d23a690.

Author: Matthew Fisher

api/tasks.py

@@ -91,7 +91,7 @@ def run_command(c, command):
         if rc != 0:
             raise EnvironmentError('Could not pull image: {image}'.format(**locals()))
         # run the command
-        docker_args = ' '.join(['--entrypoint=/bin/sh',
+        docker_args = ' '.join(['--entrypoint=/bin/bash',
                                 '-a', 'stdout', '-a', 'stderr', '--rm', image])
         escaped_command = command.replace("'", "'\\''")
         command = r"docker run {docker_args} -c \'{escaped_command}\'".format(**locals())