Bashate was not always detecting:
E004 File did not end with a newline
unless the last file processed by bashate had the violation.
This meant that zuul jobs would randomly fail.
The fix is run individually (-n 1)
Change-Id: I7934c3da82adb450fd1ba5f2630591369df8b828
Closes-Bug: 1800865
Signed-off-by: Al Bailey <Al.Bailey@windriver.com>