Update Section 4.1.4.3

Changed requirement language to suggest LRS doesn't validate Statement Object UUIDs.
Update Section 4.1.4.3

I think I was over-explaining the requirement.  The long and short is that we are asserting the scope of this requirement not be extended to the LRS, I've adjusted the language in accordance with @garemoko's comment
Merge pull request #454 from andyjohnson/master

Update Section 4.1.4.3