Remove trailing period from Styleguide section in examples and tests

[JohnAlbin]

It's fine that we should remove an optional trailing space from the Styleguide reference. But I don't see how it's useful to show them in the spec and the examples.

In this PR, I've removed the trailing space from the spec and all examples. But I've added a test that confirms that the optional trailing period is stripped.

Do we need to add a note in the spec for KSS parsers that they should strip trailing periods from Styleguide references?

[JohnAlbin]

Typo in my original test. Fixed!