qubes/tools: fix 'column' input formating

Include '\n' at the last line too. Otherwise the tool (depending on
version) will complain about truncated line ('line too long').

qubes/tools/__init__.py

@@ -524,6 +524,7 @@ def print_table(table):
     unit_separator = chr(31)
     cmd = ['column', '-t', '-s', unit_separator]
     text_table = '\n'.join([unit_separator.join(row) for row in table])
+    text_table += '\n'
 
     # for tests...
     if sys.stdout != sys.__stdout__: