Do not output colors in terraform_fmt

[senilio]

Currently the terraform_fmt formatter outputs colors, resulting in "bad" characters in conform.log.

Example:

22:03:46[ERROR] Formatter 'terraform_fmt' error: �[31m�[31m╷�[0m�[0m
�[31m│�[0m �[0m�[1m�[31mError: �[0m�[0m�[1mAttribute redefined�[0m
�[31m│�[0m �[0m
�[31m│�[0m �[0m�[0m  on <stdin> line 3, in resource "test":
�[31m│�[0m �[0m   3: 	�[4mhello�[0m = 123�[0m
�[31m│�[0m �[0m
�[31m│�[0m �[0mThe argument "hello" was already set at <stdin>:2,3-8. Each argument may be
�[31m│�[0m �[0mset only once.
�[31m╵�[0m�[0m
�[0m�[0m

Adding the -no-color argument to terraform fmt will result in a more readable output:

22:13:44[ERROR] Formatter 'terraform_fmt' error: 
Error: Attribute redefined

  on <stdin> line 3, in resource "test":
   3: 	hello = 123

The argument "hello" was already set at <stdin>:2,3-8. Each argument may be
set only once.

I know this can be added via config, but IMO this should be the default behaviour.

[stevearc]

Thanks for the fix!