Add draw=TRUE parameter to condformat2grob function

[interzoneboy]

No description provided.

[zeehio]

Thank you for the pull request

Before your pull request, the condformat2grob() tests in conformat were always creating some annoying plot windows. Now I've changed them to use draw=FALSE, to avoid the window being created. This is very convenient for all condformat contributors (myself included). Besides, the test output is now checked automatically using vdiffr, so if something breaks or changes we will notice.

Thank you very much for this.

[interzoneboy]

This makes me very happy. This is a very useful package, and honestly when is anything in life this easy to fix? =)
Also this was my first "real" experience opening an issue, submitting a pull request, and corresponding on here. I had to figure out how to do all that (obviously it wasn't difficult), and I'm very glad that I know all the steps now. Thanks for nudging me to do this!