Append a line break after captured log sections

The content in log sections doesn't always include a trailing newline, so this includes one afterwards ensuring that the next section header is placed on a new line. If there's already a trailing newline, this has no effect as it uses `<br>`.

Author: Sam Clements

pytest_html/plugin.py

@@ -263,6 +263,7 @@ def append_log_html(self, report, additional_html):
                     converter = Ansi2HTMLConverter(inline=False, escaped=False)
                     content = converter.convert(content, full=False)
                 log.append(raw(content))
+                log.append(html.br())
 
             if len(log) == 0:
                 log = html.div(class_='empty log')