Be more tolerant about whitespace

[jgierer12]

Sometimes, a comment will be edited even if there's nothing to format because extract-gfm always inserts a whitespace after code blocks. For example, this:

```sh
echo "Nothing to format here"
```

will be transformed into this:

```sh
echo "Nothing to format here"
```
    

which will result in an unneccessary edit

Note since #4, this is reversed (always removes newline after a code block if it's not required), but the problem of unneccessary edits still exists. However, with #4 this should be much easier to fix now.