Typo in discriminator example

[ralfhandl]

Based on the proposed change to 3.1.1 in #3846 the 3.0.4 text seems to be wrong.

[handrews]

@ralfhandl there are several things that need backporting from PR #2618, this is only one of them- could you close this as it will be easier for me to backport if I don't have to split pieces out. I've added #2618 to #3626 (comment) so we won't forget it.

[handrews]

As noted in other comments, I'd prefer to port PRs as PRs and not individual lines.

[ralfhandl]

@handrews Don't find this typo explicitly mentioned in #3626 (comment), so why not just fix it by merging this trivial PR instead of risking it falling through the cracks?

Note: from my perspective 3.0.4 is the most relevant of the four spec versions we are currently working on.

[handrews]

This is now addressed on this line of the full merge resolution backport:

• Backport (3.0.4) of merge resolution from #3846 #3880