RobotParser: handle empty arguments tags (#31)
RobotParser: handle empty arguments tags (#31)

* RobotParser: handle empty arguments tags

Old versions of RF, e.g. Robot 2.8.5 (Python 2.7.9 on linux2), can
produce an output file with empty "arguments" tags, i.e. no arg child.
Parsing such file would break as ignoreUntilStarts would throw an
exception due to not finding the arg starting tag.

This fix replace usage of ignoreUntilStarts to a more manual parsing
to handle this case.

* Remove extra next() call

Co-authored-by: Adrien Abraham <8fe0e67c305e06a04be56b642d7e6cc3bc6abe8e@stormshield.eu>
Co-authored-by: Aleksi Simell <b0ad0d717a774ac4500539f162570f83a060b8fc@eficode.com>
jenkinsci/robot-plugin,jenkinsci/robot-plugin,jenkinsci/robot-plugin