Describe the bug
Not sure this is a bug. Is salt-lint meant to support linting of jinja template files that are not salt state files, e.g. sourced templated files used in file.managed states, for instance?

To Reproduce
Steps to reproduce the behavior:

1. Run salt-lint on any file named like <name[.jinja|.j2]>
2. Get result [205] Use ".sls" as a Salt State file extension

Expected behavior
Return lint result for jinja template that's not a salt state, not 205.

Desktop (please complete the following information):

• Version 0.9.2

Additional context

1c2aa5c added support to run rules against different file types, namely LANGUAGE_SLS and LANGUAGE_JINJA. However, the file extension rule doesn't specify a languages configuration, but that's presumably on purpose to avoid running into a chicken-and-egg problem.

But, if (pure) jinja linting is meant to be supported, shouldn't the (state file) extension check ignore files that bear a jinja extension only, i.e. without sls anywhere in front of it?