Additional test cases for indentation linter

Here are two additional test cases for the indentation linter. The first one works fine, the second one fails, which is likely a bug in the linter.

In my project, there are CSS blocks like 
```
.class1,
.class2 { margin: 0; }
```

With the indentation linter turned on, the second line is reported as error and needs to be rewritten as
```
.class1,
  .class2 { margin: 0; }
```
in order to pass the check. That's pretty awful syntax so I assume it's a bug.

Thoughts?