Pretty test report formatting

Please answer these questions before submitting a bug report.

### What version of godog are you using?
```
> godog -version
v0.10.0
```

### What version of Go are you using?
```
> go version
1.14
```

### What did you do?
Create a test case where a test step description is very long

### What did you expect to see?
No blank lines in the formatted output

### What did you see instead?
lots of blank lines in the formatted output

### Additional context
-

Start by reproducing the report with a test step description long enough to trigger the extra blank lines, using godog v0.10.0 and Go 1.14 as the reported environment. Trace the formatter or report-output entry point and verify that the corrected output contains no unintended blank lines for long steps.

Written by the indexing model from the issue text.